STUDENT MISCONCEPTIONS CELESTÉ VAN NIEKERK …

STUDENT MISCONCEPTIONS

IN A HIGH STAKES GRADE 12 PHYSICS EXAMINATION

by

CELESTÉ VAN NIEKERK

DISSERTATION

submitted in accordance with the

requirements for the degree of

MASTER OF EDUCATION

in the

FACULTY OF EDUCATION

at the

UNIVERSITY OF JOHANNESBURG

SUPERVISOR: Dr. U Ramnarain

CO-SUPERVISOR: Dr. JJJ de Beer

NOVEMBER 2011

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DECLARATION

I declare that the work contained in this dissertation is my own and all the sources I

have used or quoted have been indicated and acknowledged by means of references. I

also declare that I have not previously submitted this dissertation or any part of it to any

university in order to obtain a degree.

Signature: __________________________

(Celesté van Niekerk)

Johannesburg

November 2011

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ACKNOWLEDGEMENTS

Firstly, I wish to thank My Lord and Saviour Jesus Christ for granting me all that I

needed to complete this study and for always being with me.

I dedicate this research study to my husband and two sons. Carel, Carel Jnr. and Allan

continuously supported and motivated me throughout this study. I would not have been

able to complete this study without their love, understanding and help.

In particular I would like to thank my supervisor, Dr Umesh Ramnarain, for his

invaluable support and academic guidance. At times when I felt like giving up, he

remained patient. I also would like to thank Dr JJJ de Beer for his contribution as co-

supervisor.

I sincerely thank the National Research Foundation and the University of Johannesburg

for their financial support.

I wish to express my gratitude towards my family, friends and “omgee-groep” for all their

support and encouragement throughout this study. I am especially grateful to my

parents, Maureen and Errol Gunn, and my in-laws, Gerrie and Cielie van Niekerk, for

their encouragement and support throughout this study. Their example of diligence and

dedication has shown me that through perseverance anything is possible.

I also would like to thank Leunis van Rooyen for his skilled editing, done in a very

professional manner.

A special word of thanks and appreciation goes to the teachers and students who

voluntarily participated in this study. Without their co-operation this study would not

have been possible.

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SYNOPSIS

The grade 12 Physical Sciences students of 2008 were the first group of South African

students to write a National Senior Certificate (NSC) on the new outcomes-based

education (OBE) curriculum – the National Curriculum Statement (NCS). Society

scrutinised the performance of students in this high stake examination. The outcome

was disappointing: 71,3% of the students achieved a mark of less than 40%, and 45%

of the group achieved a mark of less than 30%. Concern amongst the educational

community, specifically the Department of Education (DOE), initiated a request for

research into the possible causes of the poor performance by students in this

examination.

There are many factors that affect the performance of students, including the

misconceptions held by students regarding subject content. This study aims to

contribute knowledge about the common misconceptions held by science students

regarding Physics. It also investigates the performance of students in explanation-type

questions and what explanation-types reveal about student misconceptions. The

research design for this study is a content analysis which was carried out qualitatively in

two phases. In the primary phase, a sample of student examination scripts was

analysed. During the secondary phase, interviews were conducted with grade 12

Physical Sciences students and teachers from one school.

The findings of this study are that the following misconceptions are commonly held by

students:

• Heavier objects exert more force on lighter objects during a collision;

• Total external resistance decreases when an external resistor, connected in

parallel, is removed;

• Energy is lost in certain situations;

• A split-ring is found in an AC generator;

• The voltage increases when appliances are added to a multi-plug.

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The misconceptions identified in this study were revealed in explanations that students

constructed in response to examination questions. The data indicate that students

perform 8,4% more poorly in explanation-type questions than in other types of

questions. In addition, 89,3% of student explanations which revealed misconceptions

were genetic, mechanical or functional explanations. These explanation-types exposed

misconceptions about what happens in certain situations, the effect certain physical

properties of objects have on a situation and the function of certain objects,

respectively. In these types of explanations students do not relate the physical evidence

of a situation to the laws of Physics, thereby failing to provide the evidence required in a

scientific explanation. A few student explanations which revealed misconceptions were

rational explanations (1,3%). These explanations revealed misconceptions regarding

the relationship between the physical properties of objects and the laws of Physics.

Currently, the focus of assessment in Physics is on the rote learning of exemplar-type

calculations. The focus of assessment should be changed so that it targets conceptual

understanding. The in-service training of teachers regarding the remediation of

students’ misconceptions is also a recommendation of this study. In addition, since

misconceptions cannot simply be removed from the conceptual framework of a student,

the researcher recommends that the curriculum be narrowed. This will grant teachers

and students the time needed to develop a deeper conceptual understanding of

Physical Sciences.

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TABLE OF CONTENTS

CHAPTER 1

1.1 Introduction 1

1.2 Background to the research problem 1

1.3 Motivation for this study 3

1.4 Aims, objectives or purpose of the inquiry 4

1.5 Research design and methodology 5

1.5.1 Research design 5

1.5.2 Research methodology 7

1.5.3 Data collection 7

1.5.4 Data analysis 8

1.6 Compliance with ethical standards 9

1.7 Outline of the remainder of the thesis 10

CHAPTER 2

2.1 Introduction 11

2.2 Scope of the literature review 11

2.3 Defining the key concepts 12

2.3.1 Pre-knowledge 13

2.3.2 Misconceptions 14

2.3.3 Explanation 15

2.4 Theoretical and conceptual framework 18

2.4.1 Constructivism 18

2.4.2 Social constructivism 19

2.4.3 Conceptual change 21

2.4.4 Classification of explanation-types 25

2.5 Literature review 34

2.5.1 The nature of misconceptions 34

2.5.2 Sources of misconceptions 37

2.5.3 The relationship between language and misconceptions 39

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2.5.4 The relationship between assessment and misconceptions 41

2.5.5 The relationship between context and misconceptions 47

2.5.6 Misconceptions within the field of Physics 49

2.5.6.1 Misconceptions regarding Newton’s Laws on Motion 49

2.5.6.2 Misconceptions regarding momentum and kinetic energy 53

2.5.6.3 Misconceptions regarding the conservation of energy 56

2.5.6.4 Misconceptions regarding electricity and electromagnetism 58

2.5.7 Strategies for the identification and reconstruction of misconceptions 59

2.5.7.1 Concept maps 60

2.5.7.2 Writing activities 61

2.5.7.3 Group discussions and debates 62

2.5.7.4 Practical investigations 64

2.6 Conclusion 65

CHAPTER3

3.1 Introduction 68

3.2 The structure to be constructed – research questions 69

3.3 Beliefs regarding the knowledge to be constructed – epistemology 69

3.4 Research plan for the construction of knowledge– research genre 71

3.5 Construction process - research methodology 72

3.6 Collecting materials – Data collection 73

3.6.1 Exam-script data 74

3.6.2 Interview data 74

3.6.2.1 The rationale behind using interviews to supplement

the exam-script data 74

3.6.2.2 Surveying the site 75

3.6.2.3 Gaining entry and acquiring permission – ethical concerns 75

3.6.2.4 Pre-interview testing for the purposive sampling of

interview participants 77

3.6.2.5 Choosing discursive interviews as the research tool 79

3.6.2.6 Planning the interviews 80

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3.6.2.7 Interview procedure 81

3.6.2.8 Recording the interview data 83

3.6.2.9 Follow-up communication with the interview participants 84

3.7 Constructing evidence – Data analysis 84

3.7.1 Qualitative analysis of the exam-script data 84

3.7.1.1 Identifying the misconceptions 85

3.7.1.2 Designing the classification-grid 86

3.7.1.3 Preliminary classification 87

3.7.1.4 Further classification of student responses

in the sample of exam scripts 91

3.7.2 Quantitative analysis of the exam-script data 91

3.7.3 Computer Assisted Qualitative Data Analysis 92

3.8 Cleaning up the construction site – Data Storage 97

3.9 Conclusion 97

CHAPTER 4

4 .1 Introduction 98

4.2 Student performance in explanation-type questions 98

4.3 Distribution of explanation and non-explanation questions 100

4.4 Describing the different types of misconceptions and their frequency 101

4.5 Five common misconceptions 107

4.5.1 The frequency of five common misconceptions 107

4.5.2 The nature of five common misconceptions 108

4.5.2.1 First common misconception: heavier cars exert more impact

on lighter cars during a collision 109

4.5.2.2 Second common misconception: total external resistance decreases

when an external resistor connected in parallel is removed 114

4.5.2.3 Third common misconception: energy is lost 117

4.5.2.4 Fourth common misconception: a split-ring is found in

an AC generator 120

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4.5.2.5 Fifth common misconception: the voltage increases when

appliances are added to a multi-plug 122

4.6 Other misconceptions 124

4.6.1 Forces acting on two separate interacting bodies can be added,

and may add up to zero, causing the bodies to remain stationary 124

4.6.2 Light objects have less momentum and experience a greater

change in momentum during a collision 125

4.6.3 Momentum is lost or converted into heat or some other form of

energy and kinetic energy and momentum is the same property of motion 126

4.6.4 Misconceptions regarding the internal voltage of a battery 127

4.6.5 The potential difference across resistors connected in parallel remains

constant when one of the resistors is removed 128

4.6.6 DC motors and generators have slip rings and motors and

generators are the same type of machine 128

4.6.7 A cut- off switch works just like a normal switch, it can be switched

off to save electricity 130

4.6.8 Household appliances such as those connected to a multi-plug are

connected in series 130

4.7 Interpretation of the results regarding possible sources of misconceptions 131

4.7.1 The individual as a source of misconceptions 131

4.7.2 Social interactions as a source of misconceptions 132

4.7.3 Language as a source of misconceptions 134

4.7.4 Assessment as a source of misconceptions 136

4.7.5 Context as a source of misconceptions 137

4.7.6 Graphical representation of the possible sources of misconceptions

and their link with misconceptions 140

4.8 Conclusion 143

CHAPTER 5

5.1 Introduction 144

5.2 Summary of major findings 145

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5.2.1 Common misconceptions in Physics 145

5.2.2 Student performance in explanation-type questions 146

5.2.3 What explanation-types reveal about misconceptions 147

5.2.3.1 Explanation-types reveal the nature of misconceptions 147

5.2.3.2 Explanation-types reveal the sources of misconceptions 149

5.3 Implications for teachers and other role-players in education 150

5.4 Critique of the Study 154

5.5 Recommendations for future studies 155

5.6 Summary 156

REFERENCE LIST 157

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LIST OF FIGURES

FIGURE PAGE

Figure 2.1: Dagher and Cossman’s organising scheme for explanations 27

Figure 2.2: The nature of misconceptions – stumbling blocks or

stepping stones 35

Figure 4.1: A bar graph of the performance of a sample of students 99

Figure 4.2: A pie chart of the question-types in the NSC 2008

Physics examination 101

Figure 4.3: A bar chart of the frequency of misconception-types in

a sample of student exam scripts 104

Figure 4.4: A bar graph of the frequency of common misconceptions

as revealed in a sample of student exam scripts 107

Figure 4.5: An examination question on the collision between two cars 109

Figure 4.6: An examination question on a circuit diagram of three

external resistors 115

Figure 4.7: An examination question on a hydro-electric power plant 118

Figure 4.8: An examination question on a generator 121

Figure 4.9: An examination question on a cut-off switch 122

Figure 4.10: A concept map illustrating the relationship between

misconceptions and the causes of misconceptions 141

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LIST OF TABLES

TABLE PAGE

Table 2.1: Comparisons between various authors’ explanation-types 32

Table 3.1: Final misconception classification-grid 90

Table 3.2: Analysis codes 93

Table 3.3: Code families 95–96

Table 4.1: Types of responses identified in a sample of student

exam scripts 103

Table 4.2: Types of student responses classified per examination question 108

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LIST OF APPENDICES

APPENDIX DESCRIPTION PAGE

Appendix A Ethical Clearance from UJ 177

Appendix B Approval form to conduct research from DOE 178

Appendix C Permission letter to conduct research from DOE 180

Appendix D Letter of consent to school principal 181

Appendix E Letter of consent to science teachers 182

Appendix F Letter of consent to parents/guardians 183

Appendix G Letter of assent to students 185

Appendix H 2008 NSC Physics examination 186

Appendix I Possible answers for the 2008 NSC Physics examination 202

Appendix J Pre-interview test 228

Appendix K Extended memorandum for pre-interview test 232

Appendix L Exemplars of classification-grid data 239

Appendix M Questionnaire schedule for interviews 243

Appendix N Transcripts of student interviews 248

Appendix O Transcripts of teacher interviews 322

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LIST OF COMMONLY USED ACRONYMS

C2005: Curriculum 2005

DOE: Department of Education

GDE Gauteng Department of Education

OBE: Outcomes-Based Education

NCS: National Curriculum Statement

NSC: National Senior Certificate

RNCS: Revised National Curriculum Statement

UJ: University of Johannesburg

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CHAPTER 1

INTRODUCTION TO THE STUDY

1.1 INTRODUCTION

This study investigates the common misconceptions held by South African grade 12

(17-18 years) Physical Sciences students, regarding Physics. It also explores the

performance of students in explanation-type questions, the type of student explanations

which reveal misconceptions and what explanation-types reveal about student

misconceptions. The misconceptions identified in this study were extracted from

students’ explanations and were classified according to a framework of explanation-

types generated by Dagher and Cossman (1992). The study is framed in the

constructivist learning theory of social constructivism, according to which knowledge,

including misconceptions, is a social construct.

1.2 BACKGROUND TO THE RESEARCH PROBLEM

The grade 12 students of 2008 were the first group of students to write a national

examination on a curriculum which is underpinned by outcomes-based education

(OBE). This revised curriculum, called the National Curriculum Statement (NCS), was

introduced in 2003, following a series of curriculum-related reforms, including

Curriculum 2005 (C2005).

C2005 had the following three design features: transformational outcomes-based

education (OBE), integration of knowledge and learner-centred pedagogy (Chisholm,

2004). Outcomes-based education focuses on outcomes or results that students need

to achieve; instead of rote learning of subject content it encourages the development of

skills and the use of information on higher levels than recall (Mason, 1999).

Conventional school subjects were replaced by eight learning areas to ensure

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integration of knowledge in and between different disciplines (Cross, Mungadi &

Rouhani, 2002). Learner-centred pedagogy removes the focus from the transmission of

knowledge by the teacher towards the facilitation of co-discovering knowledge together

with the students. From the outset, all three of the design features and C2005 as a

whole received both a large measure of support and criticism from a range of stake-

holders. The major objections were the complex language the OBE curriculum was

written in, the marginalisation of curriculum content, increased administrative burdens

and loss of control by teachers in classrooms due to a learner-centred pedagogy

(Chisholm, 2004; Cross et al., 2002; Jansen, 1998).

A review of C2005 in 2000 directed the way forward to the design of the Revised

National Curriculum Statement (RNCS) in 2002, and the National Curriculum Statement

(NCS) as it is known today (Chisholm, 2005). The NCS is a less radical form of OBE in

that it clearly defines the core knowledge that needs to be covered in each learning

area.

Despite considerable curriculum changes, the 2008 National Senior Certificate (NSC)

Physical Sciences examinations were similar in structure and question-types to papers

based on the previous syllabus (NATED550). The main difference was that new topics

which had been introduced into the curriculum were now examined.

The performance of students in Physical Sciences was poor. Of the 218 156 students

who wrote the paper, 98 060 students (45% of the total) achieved below 30%, and only

62 530 (28,7%) achieved 40% and above (Department of Education, 2008). The poor

performance of Physical Sciences students in the 2008 NSC examinations was of great

concern to both the educational community and to society in general. This lead to the

Department of Education (DOE) requesting that the University of Johannesburg (UJ)

conduct an exam-script analysis to investigate the possible causes of poor performance

in subjects such as Physical Sciences. While factors such as curriculum change, lack of

educational resources and inadequate teacher training inevitably contributed to the

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problem, this study focuses on student misconceptions and the nature of student

explanations.

1.3 MOTIVATION FOR THIS STUDY

Poor results in Physical Sciences education have often been ascribed to students’

misconceptions. Students come to school with a collection of life-experiences, ideas

and explanations for the physical world in which they live (Driver, 1983; Posner, Strike,

Hewson & Gertzog, 1982). These concepts or ideas are commonly referred to as

preconceptions. Many of these experientially and socially constructed conceptions are

different to the scientific concepts that are taught in the Physical Sciences classroom,

so they are referred to as misconceptions. Since these misconceptions work in the

context of the students’ observations, students “cling rigidly to their current beliefs”

(Pine, Messer & St. John, 2001, p.83) and are hesitant to accept scientific concepts.

During examinations, students formulate responses based on their understanding.

Since misconceptions form part of their understanding and differ from scientific

conceptions, students formulate incorrect responses which negatively affect their

performance.

Alternative ideas or misconceptions also arise in the classroom when students interact

with their peers, teachers and learning material such as textbooks. In these interactions

students may be presented with incorrect conceptions, which they then make their own.

Sometimes teachers and textbook writers use analogies to illustrate a concept and then

students may take these analogies too far and be unable to separate it from the original

subject content; other students only remember the analogy and struggle to remember

the original content (Thiele, Yenville & Treagust, 1995). When students apply concepts

which they have learnt in the class or from experience to situations where they do not

apply, such over-generalisations also constitute misconceptions. Students may even

take a correct explanation and construct their own incorrect conception that makes

sense to them. Students’ misconceptions often go undetected and may only reveal

themselves when students write a test or an examination. Since misconceptions are

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also formed in class and are not easily recognised, it is important to increase teacher-

awareness of misconceptions by identifying specific misconceptions held by students.

In addition, Pine et al. (2001) warn that even when teachers are aware of student

misconceptions they do not necessarily have the time to investigate how their students

developed them or how to address them. Therefore it is important not only to identify

misconceptions but also to further investigate their nature, thereby constructing

knowledge that could be used in the design of remediation strategies. According to

Zuzovsky and Tamir (1999, p.1101) “Explanations are demonstrations of understanding

and provide a window to a person’s thinking.” Hence, in order to determine more about

the nature of student misconceptions, which form part of a students’ understanding, this

study explored student explanations and their connection with the misconceptions

revealed in them.

The new curriculum is student-centred as it conceives of the student as one who

constructs and applies scientific knowledge (Department of Education, 2003). The

teaching and learning approaches implicit in the new curriculum are largely founded

upon the basic tenets of social constructivism, according to which knowledge is initially

attained through social interactions after which it is internalised (Vygotsky, 1978). In

adopting a social constructivist approach in classrooms, it was expected that students

would have the opportunity to express and exchange ideas with peers and the teacher

on a particular topic. Students would then be in a position to test the degree of fit

between their preconceptions and the scientific explanations of phenomena and

reconstruct their conceptions where necessary. However, the poor results of 2008

indicate that misconceptions continue to form part of students’ conceptual frameworks

and may not be receiving the required attention.

1.4 AIMS, OBJECTIVES OR PURPOSE OF THE INQUIRY

The aim of the study is to contribute knowledge about the common misconceptions held

by Physical Sciences students, as evidenced by the 2008 NSC Physics examination. I

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also aim to investigate the performance of students in explanation-type questions, the

types of student explanations which reveal misconceptions and also what explanation-

types reveal about student misconceptions. In this regard the following research

questions were formulated:

1. What are the common student misconceptions that are revealed in a high stakes

Physics examination?

2. How do students perform in explanation-type questions?

3. What do explanation-types reveal about student misconceptions?

1.5 RESEARCH DESIGN AND METHODOLOGY

In this section I will commence by discussing the research design of this study, then I

will discuss the methodology employed to carry out the study as designed. Next I will

discuss the data collection and analysis methods which enabled me to collect evidence

regarding student misconceptions as revealed in explanations.

1.5.1 Research design

An appropriate research design and methodology yields evidence which accurately

addresses the research problem. Mouton’s advice (2009) regarding the selection of a

research design and methodology is that researchers first consider what beliefs they

hold regarding the evidence they are searching for as well as what type of evidence

they are searching for.

I approached this study from the belief that knowledge, including explanations and

misconceptions, is not merely transferred to the student but rather co-constructed by the

student and various social role-players (Vygotsky, 1978). In other words, I framed this

study in the epistemology of social constructivism.

I employed Mouton’s three pairs of design logics (2009), which are formulated to assist

researchers in deciding what type of evidence they require so that a suitable research

design can be selected. Mouton’s first pair of design logics is contextualisation versus

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generalisation. Contextualisation refers to the generation of research data which is more

detailed and focussed on a small number of cases. Generalisation refers to the

generation of research data which is applicable to a wider population. For the purpose

of this study I chose to focus on a small number of cases for a more in-depth

investigation, thereby situating this study in the logic of contextualisation.

Mouton’s second pair of design logics is discovery versus validation. Discovery refers to

the generation of research data through a process of discovery, whereas validation

refers to the generation of research data through the testing of a hypothesis. I chose to

discover more about misconceptions rather than to test a specific hypothesis regarding

misconceptions.

Mouton’s third pair of design logics is synchronicity versus diachronicity. Synchronicity

refers to the generation of data which represents a process, whereas diachronicity

refers to the generation of data which represents a specific moment in time. I chose to

generate data which would represent the development of student misconceptions and

explanations over a period of time, in other words ― the logic of synchronicity.

After using Mouton’s design logics to determine that the evidence I required for this

study would need to come from a small number of cases which I aimed to explore in-

depth, I was in the position to select a research design for this study. A sample of

student exam scripts from the 2008 NSC had been made available to me and I realised

that an exploration of the textual content in these scripts would expose student

misconceptions. Therefore, I decided to select content analysis as the research design

for this study. According to Berelson, as quoted by Breecher (1993, p.15), content

analysis is “a research technique for the objective, systematic, and quantitative

description of the manifest content of communication.” Therefore, a content analysis

would allow me to construct a thorough description of student misconceptions evident in

their explanations.

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In order to further illuminate student misconceptions I decided to also conduct a content

analysis of interview data, which I collected and analysed in a second phase of this

study. According to White and Marsh (2006), interview data that adds valuable evidence

with regard to the research question is suited to content analysis.

1.5.2 Research methodology

Deciding what methodology I would use to carry out the content analysis followed next.

Since this study aims to generate evidence regarding the process by which students

construct explanations and misconceptions, a qualitative methodology suits the

research design. Bogdan and Biklen (1998, p.38) explain that “The qualitative

researchers’ goal is to better understand human behaviour and experience. They seek

to grasp the processes by which people construct meaning and to describe what those

meanings are.” A qualitative methodology would not only allow me to better understand

the misconceptions that students construct, but would also allow me to position myself

inside the social world (Denzin & Lincoln, 2000) of the student as a co-constructor of

meaning. Even though my research adopted the form of a qualitative study, I collected

both numeric and textual data in order to induce or construct a description of student

misconceptions as revealed in their explanations.

1.5.3 Data collection

The data collection of both the numeric and textual data took place during the two

phases of this study. In the primary phase I collected data from a random sample of 921

grade 12 Physics exam scripts, which were provided by the Gauteng Department of

Education (GDE). These scripts were made available as a result of a script analysis

project being conducted at UJ for the GDE. I only collected data from the student

responses to explanation-type questions, as calculation-type questions do not provide

descriptions of students’ misconceptions and I aimed to investigate what explanations

reveal about misconceptions.

The aim of the second phase of this study was to further clarify the data collected from

the exam scripts by conducting interviews with grade 12 students and teachers. During

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interviews I would be able to probe students’ ideas regarding the misconceptions

revealed in their exam scripts. However, since I did not have access to the students of

2008, I needed to identify students from a later cohort who displayed the same

misconceptions as those presented by the 2008 cohort. Selecting a sample of research

participants for a specific purpose, such as finding students with similar misconceptions,

requires a purposive sample. In order to enable the selection of the purposive sample, I

administered a test to a group of 2010 grade 12 Physical Sciences students from a

school which is conveniently located close to my place of work. The test consisted of

the same explanation-type questions, extracted from the 2008 NSC Physics paper, that

I had collected data from in the exam scripts. After the students wrote the test I

analysed the test scripts in the same manner as the 2008 exam scripts. This enabled

me to identify students who displayed the same types of misconceptions as the 2008

cohort of students. These students constituted the sample for my interviews. The

interviews provided a richer description of the misconceptions and were also used to

seek an explanation of how students develop these misconceptions. Thereafter, the

teachers of these students were interviewed. The teachers were asked for their opinion

on the misconceptions held by their students, possible sources of misconceptions and

about the strategies they are using to address these misconceptions.

1.5.4 Data analysis

In this study the data analysis also took place in two phases. First, a qualitative and

quantitative analysis of the exam-script data was conducted. Then a qualitative analysis

of the interview data and its relationship with the exam-script data followed.

The qualitative analysis of the exam scripts commenced with the identification of

misconceptions. Student responses were compared to the memorandum. Responses

that differed from the correct answer were classified as misconceptions. Since this study

aims to investigate the relationship between misconceptions and explanations, I then

designed a grid which would be employed to categorise different types of explanations.

The categories of explanation-types were taken from the Dagher and Cossman (1992)

framework of explanation-types. Each exam-script response constituting a

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misconception was then categorised according to the type of explanation in which the

misconception had appeared. I tested the reliability of my analysis by asking another

researcher and two Physical Sciences teachers to apply the framework in categorising

student misconceptions in the exam-scripts. Through discussion we attained consensus

with regard to the classification of misconceptions found in the exam-scripts. Intercoder

reliability was 86%.

The quantitative analysis of the exam scripts commenced with a calculation of the total

number of each type of misconception and the total number of misconceptions all

together. I also calculated the average percentages achieved by the students for

explanation-type questions and for non-explanation-type questions in the examination.

After the interviews with the students and teachers I used the qualitative analysis

methods of coding and clustering to construct findings regarding the students’

misconceptions. Coding and clustering involves the breaking-down, conceptualisation

and reconstruction of the data (Strauss & Corbin, 1990). In order to reconstruct or

recontextualise the data I needed to make meaning of the data. Making meaning of the

data or constructing findings involves discussing the clusters or themes and making a

case as to how these themes are the answer to the research questions (Henning et al.,

2004). In order to improve the management of the data analysis, I used the computer

software Atlas.ti.

1.6 COMPLIANCE WITH ETHICAL STANDARDS

In my study I have complied with the ethical standards of the university. I have done this

by informing and seeking permission from the head office (Appendix B) and relevant

district office of the GDE to conduct research at a school (Appendix C). Permission for

the analysis of the 2008 grade 12 scripts was granted by way of a script analysis project

that was commissioned by the GDE. Written consent was obtained from the school

principal, teachers and parents of students who participated in the study (Appendix D –

F). Students who agreed to participate signed an assent letter (Appendix G). The letters

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informed participants of the background and purpose of the study. The potential benefits

of the findings of this study were pointed out to the participants. An explanation was

also provided regarding the nature and duration of the test and interviews. The identity

of the participants and the information obtained was kept confidential. Participants were

assured that the study would not expose them to harm in any way. Participants were

made aware that their participation is voluntary and that they could choose to withdraw

from the study at any time. The teachers and students received feedback on the

findings of the study. It is expected that the findings will inform teachers and students

about common misconceptions and how these misconceptions develop. This

information and the recommendations emanating from the study could be of value to

them in addressing these misconceptions. Data was stored in such a manner as to

ensure the confidentiality of participants and it will be kept under lock and key for two

years after the study, and thereafter it will be destroyed. The letter of ethical clearance

that was obtained for this study is included as appendix A.

1.7 OUTLINE OF THE REMAINDER OF THE THESIS

In this section I will discuss briefly how my thesis will unfold and I will indicate the main

topics that I will discuss in each of the remaining chapters.

In chapter two I have compiled a literature review of what research says regarding

student misconceptions.

Chapter three is a discussion of my research design and the method which I used to

collect and analyse data which would inform my research question.

Chapter four is a discussion of the data collected and an interpretation of what the data

means.

Chapter five is a summary of my findings, implications for teachers and other role-

players and a critique and summary of this study.

11

CHAPTER 2

LITERATURE REVIEW, THEORETICAL AND CONCEPTUAL FRAMEWORK

2.1 INTRODUCTION

The purpose of this chapter is to discuss the research trends and theories that form the

theoretical framework or scaffolding of my research problem. My research aims to

identify common student misconceptions as revealed in a Physics examination, and to

classify these misconceptions according to the type of explanation offered. Since there

are many theories regarding misconceptions and explanations, I will commence this

chapter by discussing the scope of my literature review. Thereafter, I will define the

concepts of pre-knowledge, misconceptions and explanations which are central to my

study. I will also discuss how the learning theories of constructivism, social

constructivism and conceptual change explain that knowledge, including

misconceptions, is constructed and re-crafted by a student, together with society. Next, I

will discuss the explanation classification framework which forms the conceptual

framework of my study. I will continue by reviewing literature on the nature of

misconceptions, the sources of misconceptions, the relationship between

misconceptions and language, assessment and context. I will list common

misconceptions held within the field of Physics as identified in previous studies. The

identification and remediation of misconceptions should form part of teaching, hence I

will discuss contemporary teaching methods designed to address misconceptions.

Finally, I will conclude the chapter with an overview of the main conclusions that I have

reached on the basis of my literature review.

2.2 SCOPE OF THE LITERATURE REVIEW

There is an abundance of literature and research studies on the topic of

misconceptions, thus it is necessary for me to discuss the scope of my literature review.

From my initial literature review it became evident that students enter the classroom

12

with preconception and then continue to construct concepts which often differ from the

accepted scientific concepts. It also became evident that strategies for the remediation

of misconceptions have been the topic for many research studies over the last few

decades. Initially strategies for the remediation of misconceptions were based on the

learning theories of empiricism and behaviourism, and the removal and replacement of

misconceptions was proposed. However, traditional studies showed that

misconceptions are resistant to change, even after the use of various teaching methods

designed to remove misconceptions. Contemporary learning theories, such as

constructivism, social constructivism and conceptual change, offer an alternative view

on the nature and remediation of misconceptions. Studies on constructivist teaching

strategies have shown them to be effective in addressing misconceptions. Therefore, I

will focus my literature review on the theories of constructivism, social constructivism

and conceptual change, and on the alternative views which these theories offer with

regard to the nature and remediation of misconceptions.

Research studies on misconceptions are not only based on many different learning

theories but also on many different subject fields. Since my study aims to identify

misconceptions as revealed in a high school Physics examination, I will focus my

literature review on studies that investigate misconceptions within the field of high

school Physics. I have done this because misconceptions, sources of misconceptions

and some of the remediation strategies are more subject specific.

My study also aims to investigate how misconceptions can be classified according to

the type of explanation offered. Therefore, the scope of my literature review also

includes studies on various types of explanations using the Dagher and Cossman

(1992) framework of explanation-types.

2.3 DEFINING THE KEY CONCEPTS

The key concepts that I investigated during this study are pre-knowledge,

misconceptions and explanations. In this section I will review information regarding

13

these concepts from previous studies, and supply working definitions of these concepts

for the purpose of this study.

2.3.1 Pre-knowledge

The word pre-knowledge consists of the prefix: pre, meaning before, and the root:

knowledge, meaning information, facts or understanding (Sinclair, Hanks & Fox, 1988).

Hence I will use the following definition for this study: pre-knowledge is a prior

understanding. These prior understandings are also referred to as “preconceptions”

(Morrison & Lederman, 2003, p.849). According to Novak (2004, p.23), a conception or

concept can further be defined as “perceived regularities or patterns in events or

objects, or records of events or objects, designated by a label, usually a word.”

Students come to school with a collection of prior understandings in the form of life

experiences, ideas and explanations of the physical world in which they live (Posner et

al., 1982). Mintzes, Wandersee and Novak (1998, p.75) explain that “students develop a

set of well-defined ideas about natural objects and events before they arrive at the

classroom door.” Children also construct these ideas when asking family members or

acquaintances about how and why things happen (Kibuka-Sebitosi, 2007). Students

also construct pre-knowledge inside the Physical Sciences classroom. During the

various teaching and learning activities that take place at school, students construct

their own version of the scientific concepts under discussion. These understandings

develop as the student engages with the learning material, the teacher, and with other

students (Mintzes, et al., 1998; Morrison & Lederman, 2003).

Pre-knowledge, constructed both outside and inside the school environment, forms the

foundation for constructing new knowledge (Smith, diSessa & Roschelle, 1993). Novak

(1998, p.xix) quotes Ausabel’s well-known reference which explains that “the most

important single factor influencing learning is what the student already knows.” Moore

and Harrison (2004, p.14) add that “teaching strategies that explore prior knowledge are

essential to ascertain the kinds of images and ‘talk’ that children use when constructing

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their ideas about science and how ‘things’ work.” Hence it is vital that teaching is based

on the students’ conceptual networks (Glaserfeld, cited by Mintzes et al., 1998, p.45).

2.3.2 Misconceptions

Some of the pre-knowledge or preconceptions constructed by students are different to

the scientific concepts that are taught in the Physical Sciences classroom (Akku,

Kadayifçi, Atasoy & Geban, 2003; Dekkers & Thijs, 1998; Eryilmaz, 2002; Smith et al.,

1993; Tekkaya, 2003). Traditionally preconceptions that differ from scientific

conceptions were viewed as incorrect ideas, hence the introduction of the term

misconception, which means “wrong idea” (Sinclair et al., 1988, p.497). Misconceptions

were considered to be an obstacle which hinders learning and which needs to be

removed and replaced with the correct concepts (Palmer, 2001; Tytler, 1998). However,

studies have reported that these misconceptions are very resistant to instructional

change (Clough & Driver, 1986; Eggen & Kauchak, 2004). Akku et al. (2003, p.210)

explain that “students persist in giving answers consistent with their misconceptions

even after large amounts of instruction.”

Conversely, contemporary studies have a different perspective on the status of

students’ preconceptions which differ from scientific conceptions (Dekkers & Thijs,

1998; Tytler, 1998). Smith et al. (1993, p.153) argue that “learning requires the

engagement and transformation of productive prior resources, and misconceptions,

when taken as mistakes, cannot play that role.” In other words, student’ preconceptions,

which differ from scientific conceptions, are also seen as productive prior resources

(Pine et al., 2001), conceptions under transformation, and “anchoring conceptions” upon

which new knowledge is built (Clement, Brown & Zietsman, 1989, p.554). Hence, new

terminology was introduced to match the new status of student preconceptions which

differ from scientific conceptions. This new terminology is profuse and includes terms

such as: alternative conceptions, naïve beliefs, alternative beliefs, alternative

frameworks, naïve theories, non-scientific ideas, children’s beliefs, children’s science

and informal science conceptions (Hamza & Wickman, 2009; Smith et al., 1993; Tytler,

15

1998). These differing perspectives regarding the status and nature of misconceptions

will be discussed in greater detail in section 2.5.1.

It is, however, necessary for me to clarify my position regarding the status of

misconceptions in order to define the concept of misconception. The theory of

constructivism, which I have chosen as the framework for this study, emphasises that

“prior knowledge is the primary resource for acquiring new knowledge” (Smith et al.,

1993, p.151). Therefore, I will take the position that misconceptions are conceptions

under transformation, which should not be viewed as incorrect but rather as

preconceptions that need to be refined.

Before I finally define a misconception, it is important to note that not all mistakes are

misconceptions. Students may appear to hold a misconception when actually they are

merely using the wrong language to express their idea (Clerk & Rutherford, 2000;

Schuster, 1983). Strike (1983, p.188) argues that a misconception should be viewed as

“an assumption that is structurally important in the student’s belief system. It is

something that generates mistakes.” I will use the following definition for this study: a

misconception is a believable conception which differs from the corresponding

scientific conception. Since I view misconceptions as conceptions under trans-

formation, as opposed to incorrect conceptions, I will use a variety of terminology —

including alternative conceptions and alternative constructs—interchangeably. I will also

continue to make use of the term “misconception” despite my constructivist position as it

remains a common term that researchers employ and that teachers are well-acquainted

with.

2.3.3 Explanation

The term explanation has many synonyms, such as clarification, description,

commentary, account, reason, justification, answer, defence and vindication (Hawker &

Waite, 2001). Upon examining these synonyms it becomes clear that there are subtle

differences between them. These differences allude to the fact that a variety of

meanings are attached to the term explanation. Berland and Reiser (2008, p.27) affirm

16

that “no single definition of explanation can account for the range of information that can

satisfy a request for an explanation.” Hence, they treat the term “explanation” as an

encompassing term meaning both describe and rationalise and define an explanation as

an expression of what happened, and/or a clarification of why an event happened in the

form of reasons, evidence and logical argument. Gilbert, Boulter and Rutherford (1998a)

explain that there are many types of explanations and that the explanation which is

given depends on the type of question which is asked. I will discuss the classification of

various types of explanations in greater detail in 2.4.4. On the other hand, Zuzovsky and

Tamir (1999) argue that explanation is different from scientific description, in that

explanation brings about a different level of understanding. Also during the construction

of an explanation information is connected, whereas in a description the information is

fragmented. Scriven (1998, p.53) agrees that there is a difference between explanation

and description but argues that explanation is not “something ‘more than’ or even

something intrinsically different from informing or describing.” The difference lies in the

context in which the explanation is constructed. What would be classified as a

description in one context may be classified as an explanation in another context and

vice versa. Also, what differentiates an explanation from a description is the “known or

inferred state of understanding and the proposed explanation’s relation to it” (Scriven,

1998, p.53). Since both descriptions and explanations can increase a persons’

understanding, depending on the degree to which they are complete and correct, I will

define an explanation as follows: an explanation is a detailed description of what

happened and/or a rationalisation of why something happened.

The process of constructing explanations does amplify one’s understanding and

“Articulating and learning go hand in hand, in a mutually reinforcing feedback loop”

(Sawyer, as cited by Berland & Reiser, 2008, p.29). Also, the construction of

explanations necessitates students to find reasons and evidence for a certain claim or

event and then to align the evidence and claims. This process of constructing

explanations not only develops the student’s understanding of the subject matter,

(Berland & Reiser, 2008) but also exposes the student’s current understanding (Sevian

& Gonsalves, 2008) or misunderstanding (Graesser et al., 1996; Sevian & Gonsalves,

17

2008). Zuzovsky and Tamir (1999, p.1101) explain that “Explanations are

demonstrations of understanding and provide a window to a person’s thinking.” Hence,

student explanations can be used both during informal and formal assessment to

assess a student’s understanding, in order to inform consequent teaching activities.

According to Vygotsky, as cited by Sevian and Gonsalves (2008, p.1443), “the ability to

explain one’s understanding is often a measure of whether or not that thing has been

effectively learned.” Graesser et al. (1996, p.20) echo this sentiment by stating that

“explanatory reasoning questions have been a popular litmus test of whether students

are truly understanding material, as opposed to merely memorizing explicit information.”

Explanation is also regarded as an important learning outcome and assessment

standard in the National Curriculum Statement for Physical Sciences. The second

learning outcome for Physical Sciences states that “The student is able to state, explain,

interpret and evaluate scientific and technological knowledge and can apply it in

everyday contexts” (Department of Education, 2003, p.13). Also one of the assessment

standards, that falls under the second learning outcome, states that the student needs

to be able to “Express and explain prescribed scientific theories and models by

indicating some of the relationships of different facts and concepts with each other”

(Department of Education, 2003, p.27). Hence, explanations are requested in

examinations and in the 2008 NSC Physics examination (Appendix H) students were

prompted to use principles of Physics to explain why certain events occur.

The rationale and evidence required in a scientific explanation are scientific theories

and models (Giere quoted by Gilbert et al., 1998a). This makes constructing scientific

explanations an even more complex task as students are accustomed to using their

own reasons and theories when supplying explanations, especially when the event

under explanation is framed in an everyday context. After all, “Explaining is a human

activity whose practice long antedated the rise of modern science” (Giere quoted by

Gilbert et al., 1998a, p.92). Even when assessors clarify their expectations in

explanation-type questions, students provide no reasons or incomplete reasons

because they are not used to answering such questions and because there is a “lack of

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consistency in how the terms explain and describe are used in teaching materials”

Horwood (in Dagher & Cossman, 1992, p.362). Also, many types of explanations are

used and required in Physical Sciences education which complicates the use of

explanations, together with the variety of scientific theories and terminology which must

be mastered in order to construct these explanations. Hence, it is necessary for

teachers to educate students regarding the “basic patterns of explanation” (Zuzovsky &

Tamir, 1999, p.1120). The use of both verbal and written explanation activities, in order

to develop understanding and remediate misconceptions, is discussed in greater detail

in section 2.5.7. Finally, explanations remain an essential assessment tool,

misconception identification tool and, even more so, a teaching and learning tool for

both teachers and students.

2.4 THEORETICAL AND CONCEPTUAL FRAMEWORK

My study is supported by a theoretical and conceptual framework. Henning et al., (2004)

explain that a theoretical framework situates the study within the research field, and it

reveals the researchers’ biases or beliefs regarding their study. Since misconceptions

are formed during learning experiences, both informal and formal, this study is

theoretically framed by the constructivist learning theory of social constructivism. The

conceptual framework for my study is a classification of explanation types by Dagher

and Cossman (1992), which I used to classify student misconceptions. Since social

constructivism is related to constructivism, I will start by discussing constructivism, then

social constructivism and then conceptual change. I will continue by discussing Dagher

and Cossman’s classification of explanation types.

2.4.1 Constructivism

During the last quarter of the 20th century constructivism gradually displaced empiricist-

behaviourist-dominated learning theory, which viewed learning as the direct transfer of

knowledge from teacher to student through the senses (Klassen, 2006). According to

Klassen (2006, p.826), constructivist learning theory stands in direct opposition to the

traditional notion of learning as the transferral of knowledge, as it views the student as

19

“actively reconstructing new information in order to assimilate it into existing knowledge

structures.” Constructivism was greatly influenced by the work of Piaget and Ausubel.

According to Piaget (1970, p.2) “Scientific thought, then, is not momentary, it is not a

static instance; it is a process. More specifically, it is a process of continual construction

and reorganisation.” Ausubel (in Klassen, 2006, p.829), argued that learning becomes

more long-term when “linked in a non arbitrary substantive fashion to existing

knowledge structures of the brain.” Constructivism clearly emphasises the connection of

new knowledge to a student’s existing knowledge structures (Mintzes et al., 1998). Also,

because misconceptions form part of a student’s existing knowledge structures, they

influence the manner in which new information is processed and reconstructed. Hence,

constructivism clarifies how misconceptions affect learning and thus forms the

theoretical framework for most of the current research in the field of misconceptions

(Palmer, 2001), including this study.

Constructivism is a diverse theory of learning which includes multiple views on

knowledge construction (Gravett, 2005). Individual or radical constructivists focus on the

individual’s construction of knowledge (Klassen, 2006). I agree that student constructs

are personal and that students’ understandings or constructions will differ. However, I

argue that students do not construct conceptions in a vacuum, and both social role-

players and social factors have an effect on an individual’s knowledge constructs.

Therefore social constructivism will be particularly useful in this study on the

construction of misconceptions.

2.4.2 Social Constructivism

The elementary academic orientation for social constructivism was provided by Lev

Semenovich Vygotsky. Vygotsky (1978) argued that people initially attain knowledge

through social interactions, thereafter it is internalised through reconstruction in the

mind of the individual. According to Vygotsky (1978), a student’s learning ranges

between the conceptual constructions that a student is able to construct individually and

the conceptual constructions that a student constructs with the help of a more informed

20

person. Vygotsky (1978, p.86) named this range of learning “the zone of proximal

development.”

Since cognitive development depends on both the individual and the more informed

person, teachers can influence student constructions. They can do this by the manner in

which they convey the information, the aspects they highlight and the examples and

thought-pictures that they sketch. If the teacher allows for group discussion of the

information, these discussions will also affect the understanding constructed by each

student, in fact “peers are sometimes more effective than adults in helping an individual

construct meaning because peers are at a similar developmental levels” (Jones &

Carter, 1998, p.264). Matthews (1998, p.3) reiterates that social constructivism

“stresses the importance of the group (be it the immediate classroom or the wider

culture) for the development and validation of ideas.” Mathews (1998, p.56) also states

that social constructivist theories make use of terminology such as “social negotiation”,

which emphasises the co-construction of concepts by students and society. Prawat and

Floden (1994, p.40) explain that negotiation involves “consensus building” and “skilfully

overcoming obstacles.” Reaching consensus occurs when students share their personal

constructions and reason with their teachers and peers in order to construct new

knowledge which resembles expert knowledge. When teachers are aware of students’

personal constructions they can overcome obstacles, such as misconceptions, by

designing activities which will “be able to ground new material in that portion of the

student’s intuition which is in agreement with accepted theory” (Clement et al., 1989,

p.554). Mintzes et al. (1998, p. 50) add that teachers are “middlemen” bridging the

differences between the student’s existing knowledge structures and new knowledge.

It is not only the dialogue of validation, negotiation and mediation that takes place

directly between teachers, students and their peers that influences learning. Learning

tools such as textbooks, the learning context and environment, social language and

culture also add their voice in influencing student constructs (Gravett, 2005; Zuzovsky &

Tamir, 1999). Vygotsky (1962, p.153), particularly, emphasised the effect of language

on student constructs by explaining that “Words play a central part not only in the

21

development of thought but in the historical growth of consciousness as a whole.”

According to Scott, Asoko and Leach (2007), Vygotsky regarded the social tools of

communication as resources for personal thinking. Hence, students’ conceptual

constructs will be influenced by their language resources, specifically their lack thereof.

This is especially the case when students are receiving a formal education in their

second language (Kibuka-Sebitosi, 2007), such as the majority of students in this study.

In addition, students’ unfamiliarity with scientific language and/or confusion by the

discrepancies between everyday social language and scientific language will affect their

conceptual constructs and may lead to misconceptions. I will discuss the effect of

language on student constructs in greater detail in section 2.5.3.

2.4.3 Conceptual change

If this study was framed in the empiricist theory of transferral of knowledge, I would

proceed by discussing how teachers could erase misconceptions (Strike, 1983).

However, literature has shown that misconceptions are resistant to teaching methods

aimed at replacing misconceptions (Clough & Driver, 1986). Hence, this study which is

framed in the constructivist learning theory of social constructivism, promotes a more

contemporary view for dealing with misconceptions, namely that of conceptual change.

According to Strike (1983, p.20) conceptual change theory views “learning as the

modification of current concepts” and clarifies how misconceptions can be changed.

Since misconceptions form part of students’ current concepts they can be modified or

changed during the construction of new knowledge. Also, since teachers are co-

constructors of knowledge they can assist students in modifying misconceptions.

Conceptual change theory also clarifies how misconceptions are formed. According to

conceptual change theory, learning can be viewed as the recrafting of pre-knowledge

and misconceptions are formed when students change their pre-knowledge in an

incorrect manner.

In order to better understand how students change their pre-knowledge, both during the

formation and during the remediation of misconceptions, it is necessary to understand

22

the various levels of change that may take place. At the most elementary level, students

can simply add new concepts onto their existing knowledge framework (Smith, 2007;

Tyson, Venville, Harrison & Treagust, 1997). These new concepts may be incorrect or

linked incorrectly, resulting in misconceptions. At a more advanced level, when new

concepts are incommensurable with students’ current concepts, students reorganise

their current concepts. Posner et al. (1982) label this more radical form of change as

“accommodation”. This radical form of change needs to happen in order to remediate

misconceptions, hence I will continue by discussing the conditions for accommodation.

The four conditions for conceptual change as identified by Posner et al. (1982, pp.216-

222) are: “dissatisfaction with existing conceptions”; “intelligibility of a new conception”;

“initial plausibility of a new conception”; and “fruitfulness of a new conception”. Students

first need to experience difficulties with an existing concept before they will abandon it.

These difficulties often occur in the form of an anomaly or inconsistency which the

student cannot make sense of. Anomalies can lead to a reorganisation of a student’s

misconceptions. However, the student could alternatively choose to discard the

anomaly or to regard the observations and experimental findings backing the anomaly

as irrelevant. Students may alternatively group new concepts apart from pre-concepts

as if “Science doesn’t have anything to do with the ‘real’ world”, or change the new

concepts so that they fit in with the student’s existing concepts (Posner et al., 1982,

p.221). Hence, it is important to seek out and use effective anomalies. Secondly,

students need to experience the new conception as intelligible; in other words, they

need to understand and make sense of the new conception. This involves more than an

understanding of the component terms and symbols; it includes the internal construction

of a representation of the new theory. Thirdly, students need to experience the new

concept as believable or plausible. New concepts become plausible when they appear

to have the capacity to solve problems and anomalies that pre-concepts cannot resolve,

and when the new concepts fit in with what the student believes and has experienced.

Lastly, students need to experience the new concept as fruitful. In other words, the new

concepts should communicate useful applications and discoveries. Posner et al. (1982,

p.223) warn that these conditions may not be met in a linear order and that although

23

they describe accommodation as a radical change, it “rarely seems characterized by

either a flash of insight, in which old ideas fall away to be replaced by new visions, or as

a steady logical progression from one commitment to another. Rather, it involves much

fumbling about, many false starts and mistakes, and frequent reversals of direction.”

Posner et al. (1982, pp.214-215) also identify five different types of student

preconceptions that influence the construction of new concepts and misconceptions and

the reconstruction of misconceptions. Firstly, “anomalies” affect conceptual change,

because the nature of inconsistencies in existing concepts will influence the nature of

the replacement or reorganising concepts. Secondly, the “analogies and metaphors” in

the student’s conceptual ecology will help to make new concepts more understandable.

Thirdly, the student’s inner “epistemological commitments” regarding what the student

believes about the nature of knowledge and explanations, will influence the plausibility

of new concepts. According to Nussbaum, Sinatra, and Poliquin (2008), students are

more likely to change their misconceptions if they view knowledge as flexible. Fourthly,

the student’s inner “metaphysical beliefs and concepts”, in other words what the student

believes about the incontestable nature of the universe, will also influence the

plausibility of new concepts. Lastly, the “other knowledge” that forms part of the

student’s conceptual ecology may compete against new concepts for a place in the

student’s knowledge framework.

Posner et al. clearly focus on how the student’s inner epistemological perspective

influences conceptual change and on the rational nature of learning. Research on

conceptual change has been approached from other perspectives. Chi, Slotta & De

Leeuw (1994), for example, focus on the student’s ontological perspective, that is, the

student’s view of reality or the outside world. According to this perspective, conceptual

change involves the student changing the ontological category of a concept from the

incorrect non-scientific ontological category to the scientifically correct ontological

category (Chi et al., 1994; Tsui & Treagust, 2004). For example, students who think of

heat as a material substance need to make ontological changes to their conceptual

framework (Chi et al., quoted by Tyson et al., 1997).

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Another perspective, which cannot be ignored when one is seeking to find ways of

remediating misconceptions, is that motivational and affective variables influence

learning and conceptual change. Pintrich et al., as quoted by Duit and Treagust (2003),

emphasise that a student’s interests, attitudes, ambitions, self-worth, control beliefs,

expectations, enthusiasm and needs, together with the classroom environment affect

learning. Zusho, Pintrich and Coppola (2003) emphasise three motivational components

which need to be taken into consideration in order to stimulate conceptual change. The

first is self-worth; students who believe that they are capable of effectively completing

an activity behave in ways that promote learning. The second motivational component is

assignment value attitudes; students who believe in the value of the assignment given

to them or in the course material engage in deeper levels of conceptual change. The

third motivational component is goal orientation; students who set a goal towards

achieving assignment competence have improved motivation, which in turn positively

affects learning. The last motivational component is affect. Zusho et al., (2003) define

affect in terms of interest and anxiety. Students who are interested in a subject and who

do not have negative feelings concerning performance learn and perform better. In

order to promote conceptual change of misconceptions, it is important for teachers to

pay careful attention to the social and affective aspects of students.

Finally, it is important to consider how these theoretical models of conceptual change

can be used to accelerate conceptual change in the classroom. Conceptual change

teaching strategies are exceptionally time-consuming. Hence, the curriculum should

cover fewer topics, allowing teachers and students to investigate concepts in greater

depth and to co-construct a richer understanding (Beeth & Hewson, 1999; Shymansky

et al., 1997; Vosniadou & Ioannides, 1998). Also, since various concepts are related to

one another, curricula should follow a carefully planned sequence of topics in order to

promote understanding (Vosniadou & Ioannides, 1998). Mintzes et al. (1998) and

Vosniadou and Ioannides (1998) also argue that since conceptual change is complex

and involves the co-construction of new knowledge, teachers should promote

interaction among teachers and students, group discussions and verbal expression of

25

ideas. Although most conceptual change research is of an applied nature, the teaching

strategies developed by research are very different from routine teaching and are

seldom used outside of a research program. Duit and Treagust (2003, p.684) argue that

“what works in special arrangements does not necessarily work in everyday practice”

and that it is vital for future research to describe conceptual change strategies in such a

way that teachers can make it part of routine teaching. Millar, as cited by Scott et al.

(2007), also warns that there may be no straightforward, direct correlation between

learning theories and teaching approaches. Hence, teachers are advised to use

activities which investigate the understanding of students and which can then be used in

order to inform later teaching. In addition, researchers are advised to close the gap

between research and practise by engaging with the professional knowledge of

teachers in an attempt to develop guidelines for instructional design (Scott et al., 2007).

2.4.4 Classification of explanation-types

Before I commence my discussion on the classification of explanation-types, it is

important that I explain why I will be using an explanation classification framework to

classify misconceptions. Classifying an explanation assists one in understanding the

characteristics of the explanation and enables one to identify the misconceptions in the

explanation. Also, as previously mentioned, “Explanations are demonstrations of

understanding and provide a window to a person’s thinking” (Zuzovsky & Tamir, 1999,

p.1101). Thus, one can use a classification of student explanations to classify student

misconceptions. Just as there are a range of explanation-types, there are a range of

classification systems for explanation-types. These include Treagust and Harrison’s

(2000) framework and those frameworks which I will discuss in this section –Dagher

and Cossman (1992), Martin (1972) and Gilbert et al. (1998a). I will start by discussing

the Dagher and Cossman (1992) classification framework which I used in my study.

Therafter I will compare their classification framework to classification frameworks

created by two other researchers. Finally I will justify my choice of Dagher and

Cossman’s framework for my study on misconceptions.

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Dagher and Cossman devised their explanation framework in order to classify verbal

teacher explanations. There are sufficient similarities between teacher and student

explanations. For example, they both aim to provide an answer to a question together

with reasons for the answer, and they both represent the understanding of the person

constructing the explanation. Teacher explanations also influence the construction of

student explanations as previously discussed, hence student explanations may

resemble teacher explanations. Moore and Harrison (2004) used the Dagher and

Cossman explanation framework to effectively analyse written student explanations in

their research study on the use of reflective student explanations to enhance conceptual

learning. Hence, the Dagher and Cossman framework will be appropriate in the

classification of the written student explanations in this study.

The Dagher and Cossman (1992) explanation framework identifies the following ten

explanation-types: tautological, practical, metaphysical, anthropomorphic, analogical,

mechanical, functional, teleological, rational and genetic. In order to enable the

classification of explanations, Dagher and Cossman formulated descriptions of each

type and an organising scheme indicating the relationship between the various types of

explanations. Dagher and Cossman’s organising scheme is included as figure 2.1:

27

Figure 2.1: Dagher and Cossman’s organising scheme for explanations

Source: Dagher and Cossman (1992, p.369)

According to the organising scheme, teacher explanations can be classified as either

theoretical or atheoretical. Dagher and Cossman identified two types of atheoretical

explanations, namely tautological and practical explanations. Gilbert et al. (1998a) refer

to atheoretical explanations as “non-explanations” in their explanation framework and

attribute them to a lack of content-knowledge. Dagher and Cossman described

tautological and practical explanations as follows:

Tautological explanations answer a question by reconstructing the question, and do so

without including any new information, e.g. “Chromosomes are in pairs so that they can

pair” (Dagher & Cossman, 1992, p.366) and “it floats because it is made to float” (Moore

28

& Harrison, 2004, p.7). On analysis of student exam scripts I found tautological

explanations such as “Q, because it is a good conductor” as a response to the question:

“Which one (P or Q) is the better conductor? Explain your answer.”

Practical explanations describe how to do something. For example: “to float you need

to do …” (Moore & Harrison, 2004, p.7) and "The cut of switch is important because

when the multi-plug is over loaded switch on the cut-off switch quick", extracted from my

research data.

Rescher, as cited by Dagher and Cossman (1992, p.368), explains that theoretical

explanations are different from atheoretical explanations because an individual who

constructs a theoretical explanation “rationalizes facts and renders them intelligible.”

Theoretical explanations are divided into two categories on Dagher and Cossman’s

organising scheme, namely spurious and genuine. Spurious explanations or

“counterfeit” explanations (Gilbert et al., 1998b, p.191) are formulated in such a manner

that they cannot be proven as true or false, as opposed to genuine or authentic

explanations which are falsifiable (Trusted, cited by Dagher & Cossman, 1992). Gilbert

et al. (1998b, p.191) warn that spurious explanations may be seen as “legitimate in

certain cultural contexts.” Dagher and Cossman identified two spurious explanation-

types: metaphysical and anthropomorphic; and six genuine explanation-types, namely:

analogical, mechanical, functional, teleological, rational and genetic.

Metaphysical explanations make use of a supernatural agent as the cause, e.g., “God

made it float” (Moore & Harrison, 2004, p.7).

Anthropomorphic explanations allocate human characteristics to a non-human agent

in order to make it more familiar. For example: “she floats because she is lighter”

(Moore & Harrison, 2004, p.7). In my research data I found anthropomorphic

explanations such as "so that electrons would get time to rest when switch it on they

perform a good work.” Treagust and Harrison (2000, p.1165) view anthropomorphic

explanations as “effective pedagogical content explanations, because teachers’

29

pedagogical content knowledge is neither pure science nor is it intended to be.” They

argue that anthropomorphic explanations are used by many teachers, instead of

scientific terminology, to help students understand Physical Sciences.

Analogical explanations make use of a familiar situation to explain a similar but

unfamiliar event, for example: “it can float because it’s like a submarine” (Moore &

Harrison, 2004, p.7).

Mechanical explanations cite causal agents of a physical nature, e.g., “it floats because

of its shape” (Moore & Harrison, 2004, p.7) and an example from my research data: “the

driver of the truck will take less impact because of its size and mass.”

Functional explanations explain events in terms of their immediate consequence or

function (Dagher & Cossman, 1992). Zuzovsky and Tamir (1999, p.1103) explain that a

functional explanation “seeks to understand a behaviour pattern or property by

determining the role it plays in keeping a given system in proper working order.”

Examples of functional explanations include the following: “It floats because of the air in

it” (Moore & Harrison, 2004, p.7), “But we don’t get sick all the time because we have

immune systems that can fight them off” (Dagher & Cossman, 1992, p.364), and “the

current would increase because the resistor like slows down the current and so if it’s not

there it would like increase the current” — an example from my research data.

Teleological explanations explain events in terms of how their immediate consequence

or function contributes, through determined action with other events that are part of the

same physical system, toward the probable attainment of an ultimate consequence,

(Dagher & Cossman, 1992, p.366). Moore and Harrison (2004, p.7) provide the

following example of a teleological explanation: “boats float because we need them to

float.” The following teleological explanation is an example from this study: “the

momentum will not be conserved because the collision may be inelastic."

30

Genetic explanations describe what happens, by relating a sequence of events, and not

why something happens, e.g., “it floated on top of the water” (Moore & Harrison, 2004,

p.7), and “The linear momentum isn’t conserved when both cars move forward after the

collision and the one car moves even further forward”, extracted from my research data.

Rational explanations provide evidence for a claim, e.g., “a boat floats because the up-

thrust from the water equals the weight” (Moore & Harrison, 2004, p.7) and “Therefore

the more the mass of a car, the more the force it will apply on the lighter vehicle

because F α m", extracted from my research data.

The above ten explanation-types generated by Dagher and Cossman were

comprehensive enough to described all of the teacher explanations transcribed in

Dagher and Cossman’s study. However, Gilbert et al. (1998b) argue that Dagher and

Cossman’s framework neglects certain explanation-types which more comprehensively

represent what can be accomplished by Physical Sciences. Gilbert et al. (1998a)

derived their typology of explanations from the relationships between the nature of

questions asked and the explanations which they bring forth. They identified the

following questions asked in scientific investigations and the corresponding explanation-

types:

• Why is the inquiry to be carried out? This question produces an intentional

explanation.

• How does the phenomenon behave? This question produces a descriptive

explanation.

• Of what is the phenomenon composed? This question produces an interpretive

explanation which labels the units within the phenomenon.

• Why does the phenomenon behave as it does? This question produces a causal

explanation.

• How might it behave under other conditions? This question produces a

predictive explanation.

31

In a comparison between their typology and Dagher and Cossman’s typology, Gilbert et

al. explained that their descriptive and interpretive explanations might be seen as being

rational and analogical explanations respectively. They also grouped mechanical,

teleological, functional and genetic explanations together as being part of their causal

explanations, because they just link an action and a reaction. They did, however, argue

that this group of causal explanations represented “weak forms of causal explanation

because they contain no statement about a mechanism which links action and reaction”

(Gilbert et al., 1998b, p.191).

According to Gilbert et al. (1998a, p.87) their typology of explanations corresponds

agreeably with another explanation typology by Martin (1972), which was derived by

focusing on the activity of providing an explanation and the discourse involved in doing

so. I have summarised Gilbert et al.’s comparison in the table 2.1:

32

Table 2.1: Comparisons between various authors’ explanation-types

Ty

pe

s o

f e

xp

lan

ati

on

s

Martin Gilbert et al. Dagher and Cossman

Justification (Provision of reasons

why a belief or action is reasonable)

Intentional

Clarification (Description of how

phase relates to phenomenon)

Descriptive (Clarification of meaning)

Rational (Evidence is provided for a claim)

Gen

uin

e

Th

eo

retica

l

Citation of theory Interpretive Analogical

(Unfamiliar is described in terms of familiar)

Causal account (Propositional

statement stating why something is)

Causal

Genetic (A sequence of events are related)

Mechanical (Physical causal relationships are

given)

Functional (A phenomenon is explained in terms of

its immediate consequence)

Teleological (A phenomenon is explained in terms of

how its immediate consequence contribute towards an ultimate

consequence) Predictive

(Deduction of future events)

Attribution of function (Not based on a

question as in Gilbert’s typology)

Metaphysical (A supernatural causal agent is given)

Sp

uri

ou

s

(Fa

lse

)

Th

eo

retical

Anthropomorphic (Human characteristics are attributed to

a non-human agent)

Non-

explanation

Practical (Instructions as to how to perform

operations)

Ath

eo

retica

l

Tautological (The question is reformulated)

Source: Compiled by researcher

33

Dagher and Cossman’s framework of explanation-types is better suited to this study

because, firstly, it has been used to analyse written student explanations and detect

misconceptions (Moore & Harrison, 2004). Secondly, it makes a greater distinction

between the various types of explanations, thereby identifying explanation-types which

are excluded by other frameworks. For example, it differentiates between the different

causal explanations, those of mechanical, teleological, functional and genetic

explanations. This distinction is useful in my study on misconceptions as it reveals the

different incorrect and/or incomplete causes which students use to clarify why

something happens. Thirdly, this study involves the analysis of explanations produced

from exam questions which required only causal and descriptive type explanations. The

following questions are the exam questions, related to my study, which required causal

explanations:

• Explain why the conservation of linear momentum may NOT be valid in this

collision.

• Use principles of Physics to explain why the risk of injury for passengers in a

heavier car would be less than for passengers in a lighter car.

• Is plate B negatively or positively charged? Give a reason for your answer.

• Which one (P or Q) is the better conductor? Explain your answer.

• Using principles in Physics, explain why this cut-off switch is important.

The following are the questions that required descriptive explanations:

• Explain what happens to the 15% of the kinetic energy that is NOT converted into

electrical energy.

• Briefly describe the diffraction pattern that will be observed on the screen.

• Name ONE similarity and ONE difference in the pattern observed when the

single slit is replaced with a double slit.

• What type of generator is illustrated in the diagram? Give a reason for your

answer.

The following exam questions appear to be predictive, but since they all involve

predictions that are covered in exemplar-type questions found in textbooks they are

actually causal:

34

• Will this pattern be observed if the laser is replaced with a light bulb? Give a

reason for your answer.

• How will the reading on voltmeter V change if resistor R burns out? Give a


• State and explain what effect this increase in the intensity of incident radiation

has on the energy and number of emitted photo-electrons.

Therefore, including the intentional and predictive explanations from Gilbert et al.’s

framework would be unnecessary.

2.5 LITERATURE REVIEW

In this next section I will review studies regarding the complex nature of misconceptions

and the sources of these misconceptions. I will discuss research on the relationships

between misconceptions and language, misconceptions and assessment and

misconceptions and context. I will consider common misconceptions in the field of

Physics, as well as contemporary teaching strategies designed to aid in the

identification and remediation of misconceptions.

2.5.1 The nature of misconceptions

In section 2.3.2 I briefly discussed the differing perspectives regarding the status of

misconceptions. In this section I will continue this discussion and also discuss the other

dimensions of the multifaceted nature of misconceptions.

On the one hand misconceptions were traditionally viewed as incorrect ideas which

“conflict with accepted scientific explanations” (Mintzes et al., 1998, p.75).

Misconceptions were viewed as “barriers and misleading elements in thinking”

(Tytler, 1998, p.909), which obstruct the conceptual understanding of students

(Chittasirinuwat, Kruatong & Paosawatyanyong, 2009). Palmer (2001, p.194) explains

that misconceptions “interfere with learning” and Posner et al., (1982) argue that

misconceptions need to be replaced. Traditional studies also reported that

misconceptions are extremely persistent and resistant to change (Clough & Driver,

35

1986; Eggen & Kauchak, 2004; Driver, Guesne & Tiberghien, 1985; Mintzes &

Wandersee, 1998; Pine et al., 2001; Posner et al., 1982; Tytler, 1998), which makes

removing them problematic.

On the other hand contemporary studies argue that while misconceptions may be

different to expert scientific conceptions, they are useful preconceptions which are

still under construction, constantly evolving and thereby enabling learning (Novak,

2004; Smith et al., 1993). Misconceptions are useful as explanations of everyday

experience (Mintzes et al., 1998; Vosniadou & Ioannides, 1998). However, they are not

only useful in everyday life but also act as “useful recognition pathways into higher

order conceptions” (Tytler, 1998, p.909) or as “anchoring conceptions” (Clement et al.,

1989, p.554).

I have illustrated these opposing perspectives in figure 2.2:

Figure 2.2: The nature of misconceptions –stumbling blocks or stepping stones


As I have mentioned in section 2.3.2, I view misconceptions as useful prior knowledge

which act as stepping stones that enable students to construct a deeper understanding.

Persistent

Useful preconceptions

Conflicts with

science

Useful recognition

pathway

Enables learning Interferes with

learning

Barrier in thinking

Evolving

Incorrect ideas

Different to scientific

conceptions

Need to be recrafted (Under construction)

Need to be replaced

36

I will proceed by discussing the other characteristics of misconceptions. Misconceptions

co-exist with more advanced scientific conceptions (Alzate & Puig, 2007; Palmer,

2001; Scott et al., 2007). Viennot as quoted by Tytler (1998, p.923) explains that

intuitive and scientific conceptions co-exist even in the minds of scientists and that an

intuitive conception “reappears in the expert when he or she lacks time to reflect.” Smith

et al. (1993, p.124) also explain that “students can shift between correct and flawed

approaches within the same problem-solving episode, which suggests that cognitive

structures can embrace both expert concepts and misconceptions.” Tytler (1998, p.923)

warns that:

The existence of naive alongside more sophisticated, generalizable conceptions, should not be

seen merely in terms of the inability to apply the higher order conception in particular situations

(although this can be true, and leads to a falling back to the more naive conception), but should

be viewed in terms of these more naive conceptions forming part of a network of supportive

intuitive ideas which serve a useful function as phenomenological markers, or scaffolds.

Students may also have concurrent multiple conceptions within any one subject area

(Hamza & Wickman, 2009; Palmer, 2001). These multiple misconceptions often

depend on the context of the problem (Moore & Harrison, 2004; Tytler, 1998), hence

a particular problem context would activate a particular alternative conception and

another context would activate another alternative conception, resulting in an apparent

incoherence of the student’s response (Clough & Driver, 1986; Driver et al., 1985;

Palmer, 2001). Also, because students often make sense of their observations and

experiences in terms of their preconceptions, these preconceptions are steeped in

everyday language (Tytler, 1998).

Often scientists, teachers and students share similar intuitive conceptions as

misconceptions are shared amongst a diversity of cultures, ages, abilities,

genders, subjects and levels of experience (Alzate & Puig, 2007; Driver et al., 1985;

Mintzes, et al., 1998; Scott et al., 2007; Vosniadou & Ioannides, 1998). Intuitive

knowledge is also internally logical to the student as it is based on reasoning by the

student and observations made by the student (Driver et al., 1985; Mintzes, et al.,

37

1998). Intuitive knowledge is often hidden from both students and teachers (Mintzes et

al., 1998; Smith et al., 1993; Thompson & Logue, 2006). Students are often unaware of

the explanatory frameworks they have constructed (Vosniadou & Ioannides, 1998), and

are rarely asked to explain their thinking in class. Even when exams are designed to

probe conceptual understanding and an explanation is required, students are restricted

by short time limits and other pressures inherent in examinations and may not reveal

their misconceptions.

2.5.2 Sources of misconceptions

Without a proper understanding of how and why students come to think in the ways that

they do, “teachers have a very limited basis for planning teaching that can support

conceptual change” (Franco & Taber, 2009, p.1946). Hence, I will continue this review

of literature by investigating the sources of student misconceptions. I will commence this

review by discussing the origins of misconceptions that are internal with regard to the

student, then I will discuss external origins of misconceptions that involve various social

role-players and finally I will discuss external origins that involve tools of learning.

Since misconceptions are constructed by an individual, the individual is the primary

source of misconceptions. Driver et al. (1985) explain that students internalise their

experience in a personal manner. This is because observation, experience and

understanding are influenced by an individual’s prior beliefs and knowledge (Carr et al.,

1994; Strike, 1983). In other words, experience and observations do not cause

misconceptions; rather misconceptions cause an individual to experience and observe

reality in a manner which differs from reality. Consequently, an individual’s incorrect

interpretation of experience and observations either reinforces the initial

misconception or is used by the individual to construct a new misconception. Also, when

students apply concepts to situations where they do not apply; such over-

generalisations also constitute misconceptions (Smith et al., 1993). Pine et al. (2001)

explain that overgeneralisations are not easily abandoned because they work in certain

situations.

38

Children also ask family members, acquaintances and other members of society

about how and why things happen (Kibuka-Sebitosi, 2007, p.57). Many of these socially

constructed theories are different to the scientific theories that they learn in the Physical

Sciences class and since these alternative conceptions work in the context of the

student’s observations, students are hesitant to accept scientific concepts.

Alternative ideas or misconceptions also arise in the classroom as a result of the

interaction between students and their peers and their teachers. Students co-

construct conceptions together with the various role-players found in the classroom, by

adding onto and restructuring their pre-concepts according to the new concepts that are

introduced. Often, these constructs are incorrect or partially incorrect. During classroom

interactions students may also be presented with incorrect conceptions by peers or

even teachers (Kikas, 2004), which they then make their own. In fact, studies have

shown that teachers hold various misconceptions on topics they teach in school

(Bayraktar, 2009; Kikas, 2004).

Teachers make use of a variety of learning tools in an attempt to enrich learning; often

these tools are a source of misconceptions. For example, teachers and textbook writers

use analogies to illustrate a concept. Thiele and Treagust (1991, p.2) explain that an

“analogy can allow new material to be more easily assimilated with the students’ prior

knowledge enabling those who do not readily think in abstract terms to develop an

understanding of the concept.” However, the use of analogies in facilitating students

understanding of complex concepts has also been problematic, as the differences in the

attributes between analog and target are often a cause of misunderstanding for

students when they map unshared attributes from the analog to target (Dilber &

Duzgun, 2008; Orgill & Bodner, 2004). Also, students sometimes take these analogies

too far and are unable to separate them from the original subject content; other students

only remember the analogy and struggle to remember the original content (Thiele et al.,

1995).

39

Furthermore, the curriculum expects students to apply scientific theories to real world

problems, but a gap exists between the complexity of the real world and the

sparseness of scientific theory (Smith et al., 1993), so this leads to the formation of

misconceptions. Real world problems rarely adhere to the conditions under which

scientific theory exists; this confuses the students. Pallrand (1996, p.317) explains that

“Scientific knowledge in school often appears in a form that is abstract, formal, and

decontextualized. As a result it may be difficult to relate new knowledge to what is

already known.”

Studies on the analysis of textbooks have reported the occurrence of high levels of

misconceptions within textbooks (Hubisz, 2003; King, 2010; Stefani & Tsaparlis, 2009).

Also, the language used in textbooks and in classrooms may be another source of

misconceptions. According to Gunstone and Watts (1985. p.101) “Language which is

meaningful to teachers may, because of students’ views of the world, have a quite

different (even conflicting) meaning for students.” In other words, the incorrect use and

interpretation of language may be the source of misconceptions. Strike (1983, p.22)

argues that “We may often have little further to look for the sources of misconceptions

than how we talk.” I will discuss the effect of language on concept formation in more

detail in the next section.

It may not be possible or even necessary to eliminate these sources of misconceptions,

as misconceptions form the framework upon which conceptual restructuring takes

place. However, it remains important that teachers and students become aware of these

sources of misconceptions and, where possible, avoid reinforcing incorrect conceptions.

2.5.3 The relationship between language and misconceptions

The relationship between language and misconceptions is complex. Firstly, language

can expose misconceptions. According to Moore and Harrison (2004) when students

use different scientific terms interchangeably as if they have the same meaning, their

incomplete understanding is exposed. Secondly, when students label concepts

incorrectly because they do not have the required vocabulary to express themselves,

40

language problems can be misdiagnosed as misconceptions (Clerk & Rutherford,

2000; Kibuka-Sebitosi, 2007; Schuster, 1983). Thirdly, the incorrect use and

misinterpretation of language can cause misconceptions. I will continue this

discussion by discussing how the incorrect use and misinterpretation of language

causes misconceptions.

The incorrect use of scientific language by teachers, family, friends, the authors of

textbooks and the media can cause misconceptions, because from a social

constructivist perspective students co-construct their understanding together with these

various social role-players (Duit & Haeussler, 1994; Kikas, 2004).

The nature of scientific language is complex and abstract, making it difficult for students

to link new scientific language to existing conceptions and to construct new conceptions

without possibly constructing misconceptions. Jones and Carter (1998, p.265) explain

that students who do not understand this scientific language “fail to develop viable

concepts.” Also, understanding the language of Physical Sciences involves more than

understanding separate concepts, it involves understanding the relationship between

concepts and the language used to represent those relationships. Mastering the

scientific language is even more complex when one considers the multimodal nature of

the language of Physical Sciences. The language of Science is a combination of

“words, diagrams, pictures, graphs, maps, equations, tables, charts, and other forms of

visual and mathematical expression” (Lemke, as cited by Scott et al., 2007, p.47).

Hence, students are required to understand not only the abstract terms and

relationships between them but they must also be able to move comfortably between

graphs, mathematical relationships and the language used in scientific investigations.

Students who are required to study Physical Sciences in their second language, such

as the majority of students in this study, may struggle even more to understand abstract

scientific language as they generally have a poor command of the ordinary English that

is used to explain scientific concepts (Kibuka-Sebitosi, 2007).

41

When students do not realise the differences between the everyday and scientific use of

the words, they may construct misconceptions. White (1994) argues that

misconceptions are more prevalent for topics that make use of ordinary words in an

expert manner. Learning a new scientific meaning of an ordinary word requires students

to connect their existing everyday social language meaning to a new scientific meaning

and to change their understanding if necessary (Bryce & MacMillan, 2009). Physical

Sciences language also differs from everyday language with regard to the manner in

which reality is viewed. Physical Sciences and everyday language sometimes place the

same concept into different ontological categories (Scott et al., 2007). Students who are

unaware of these differences may hold a misconception. For example, the concept of

weight is categorised as a property of matter in everyday language and as an

interaction in Physical Sciences language.

The differences between written and spoken language also influences the formation of

misconceptions. Carlsen (2007) clarifies that talk is social whereas writing is personal.

Hence, it is important for students to practise writing explanations as a way of moving

from the social to the personal plane in order to internalise new concepts. The practise

of writing actually forms part of the process of conceptualisation, rather than a mere

transfer of knowledge. Hence, it is understandable that students with a lack of

experience in writing explanations will yield incomplete concepts. The importance of

writing activities is discussed in further detail in a following section.

2.5.4 The relationship between assessment and misconceptions

Assessment affects why, what, and how we learn; and learning, in turn, affects the

development of assessment methods and assessment results. Mintzes, Wandersee and

Novak (2001, p.123) are confident that “the way we choose to evaluate and reward

student work may be the single most significant determinant of high quality conceptual

understanding.” I will commence by discussing how assessment may negatively affect

the development of student conceptions. I will continue by discussing how assessment

can positively affect learning through the diagnoses of misconceptions and through the

remediation of misconceptions.

42

Traditionally the focus of assessment has been on testing whether a candidate has the

knowledge needed to gain entrance to the next grade, level, course or job. Hence,

traditional assessment is largely summative, occurring after teaching (Klassen, 2006;

Treagust, Jacobowitz, Gallagher & Parker, 2001). The information on student

conceptions that is gained from traditional summative assessment is used to grade the

student. Unfortunately, traditional summative assessment is not used to design

teaching strategies which could remediate misconceptions and develop

conceptual understanding.

Critique of traditional assessment also highlights the argument that traditional

assessment discourages the development of student conceptual frameworks by

over-emphasising the rote learning of facts and the solving of exemplar-type

problems. This over-emphasis “allows students to get by with rote learning” (Morrison

& Lederman, 2003, p.863) and takes the teaching focus away from the development of

deeper understanding and conceptual change, which in turn means students do not get

to develop their incomplete conceptions (Akku et al., 2003; Driver et al., 1985). Bryce

and MacMillan (2009, p.739) explain that “The commonly emphasized mechanistic,

number-crunching approach to the analysis of simple collision problems is judged to be

un-profitable” and “may be the source of many misunderstandings.” Halloun (1998,

p.239) adds that Physical Sciences students “often pass their courses without

meaningful understanding of the subject matter” and Harrison, Grayson and Treagust,

(1999, p.55) confirm that “Some high-achieving students complete physics courses with

many of their intuitive conceptions intact.” Without the pressure of having to teach to the

test, students and teachers will be able to engage in meaningful learning and even

meaningful assessment. Mintzes et al. (2001, p.118) remind us that “The way we

choose to assess student progress conveys much about what we value, and these

values are readily discerned, internalised, and acted upon by students. ...If our goal is to

encourage understanding we must make that goal clear to our students by our choice of

assessment strategies.”

43

Another problematic issue regarding traditional assessment is that traditional

assessment fragments and decontextualises knowledge. This causes students to

struggle with connecting new information to their existing conceptual framework, and

with constructing integrated cohesive knowledge frameworks that can be readily

accessed and used. Mintzes et al. (2001, p.118) warn that “we live in a strongly

interconnected world, and students will need to leave school with more than just bits

and pieces of disconnected knowledge.” Besides, Halloun (1998, p.247) adds that “An

isolated concept is practically meaningless and useless.” Furthermore, Klassen (2006,

p.832) explains that “Testing for a particular piece of knowledge in a decontextualized

manner will not tell the assessor to what degree this knowledge has been integrated

with long-term memory structures.” Nor will decontextualised and fragmented

assessment reveal misconceptions that co-exist alongside scientific conceptions, so

that they can be addressed.

The stress caused by traditional summative assessment forms part of the social

and affective variables that may negatively affect conceptual change. Klassen

(2006, p.844) clarifies that “high-stakes assessment tends to produce elevated stress

levels for teachers and students and decreased student motivation.” Students who are

stressed and unmotivated have difficulty concentrating on the construction of new

scientific concepts when their thoughts are preoccupied with fears. So they may not

make the necessary links between the new knowledge and their pre-knowledge,

resulting in incomplete conceptions or misconceptions. According to Palmer (2005)

stress may also affect the remediation of misconceptions, because the reconstruction

of misconceptions involves focussed linking of new knowledge to pre-

knowledge, and distracted students may lack the motivation to make the effort

required. Zusho et al., (2003, p.1083) explain that “worry and negative emotions about

doing well in class, has been found to have negative consequences on cognition.”

Therefore Palmer (2005) advises that concepts linked with misconceptions should not

be presented to students until they have developed a conceptual framework that will

enable them to achieve reconstruction of a misconception within a few minutes of effort.

44

Traditional assessment in Physical Sciences education consists predominantly of

methods such as “selected-response” questions like multiple choice questions, brief

“constructed-responses” and exemplar-type questions (Klassen, 2006). Mintzes et al.

(2001) warn that such 20th century methods of assessment do not effectively reveal a

student’s true level of understanding. Hence, traditional assessment often does not

expose alternative conceptions. Multiple-choice questions have been used to

diagnose misconceptions in research studies (Akku et al., 2003; Schmidt, 1997;

Tekkaya, 2003), but in these studies the distracters were chosen from previous

research on student misconceptions. So it is possible to also use multiple-choice

questions in school assessment for the purpose of diagnosing misconceptions if the

distracters target student misconceptions. Furthermore, Schmidt (1997) argues that the

use of multiple-choice tests by Physical Sciences teachers for the purpose of

diagnosing misconceptions is less time-consuming than alternative methods such as

student interviews. Clerk and Rutherford (2000), however, warn that multiple-choice

questions may not be the best method of diagnosing misconceptions because one

cannot assume that students hold a specific misconception just because they choose

the corresponding distracter. Shaw, Bunch and Geaney (2010) explain that the

students’ language proficiency affects how they answer multiple-choice assessments.

Hence, language problems may be misdiagnosed as misconceptions (Clerk &

Rutherford, 2000). In addition, whether or not traditional assessment successfully

uncovers alternative conceptions, it does not promote effective feedback regarding

students’ individual conceptions. Teachers generally only discuss the correct answer

and have little time to discuss either the distracters in a multiple-choice assessment or

alternative ideas in another form of assessment.

Despite the critique against traditional or summative assessment, it remains established

as the most popular form of assessment, because schools are subject to high stakes

external final exams of a summative nature. Hence, it continues to have a negative

effect on meaningful learning.

45

I will continue by discussing how assessment can positively affect learning. Baseline

and diagnostic assessment can be used to diagnose alternative student

conceptions. The National Curriculum Statement (NCS) (Department of Education,

2003, p.56) explains that baseline assessment is useful to “establish what students

already know and can do” and that it is helpful in the planning of learning activities; the

NCS also encourages diagnostic assessment in order to “discover the cause or causes

of a learning barrier” and to assist in “deciding on support strategies”. İngeç (2009)

argues that diagnostic assessment methods, such as concept mapping, can provide

information about students’ misconceptions which is not extracted from summative

tests. Baseline and diagnostic assessment can therefore be used by teachers to

uncover misconceptions that students have at the start of a topic and that students

develop as teaching of the topic progresses.

Despite the importance of diagnostic assessment and teachers’ awareness of the

importance of diagnosing student’s preconceptions, Morrison and Lederman (2003)

found that teachers do not use a variety of diagnostic strategies such as pre-tests,

concept maps, interviews, or journals. Also, when teachers do use diagnostic

assessment, they found that teachers usually use only informal verbal assessment or

written summative assessment in order to diagnose whether or not the student knows

the correct answer. It is not common practice to use assessment to diagnose what

misconceptions students hold and to follow up on the diagnosis by addressing the

misconceptions. Morrison and Lederman (2003) propose that the absence of diagnostic

assessment and the necessary follow-up elicited by diagnostic assessment may be as a

result of the pressure placed on teachers to complete a set amount of work in a limited

time frame; teachers may also hold beliefs that do not agree with constructivist

teaching. The implementation of the NCS was accompanied by teacher training on

alternative forms of assessment such as baseline and diagnostic assessment. However,

I argue that the curriculum is too broad and agree with Morrison and Lederman that

teachers do not have enough time to implement effective assessment.

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Even though baseline and diagnostic assessment is not common practise, it has been

shown to be an effective manner of diagnosing misconceptions. Treagust, Jacobowitz,

Gallagher and Parker (2001) report that Gallagher, a teacher, effectively used a written

pre-test consisting of open-ended questions as well as a diagnostic question at the start

of each lesson, oral feedback and embedded written activities in order to assist her in

identifying alternative student conceptions.

Assessment can be used, not only to diagnose misconceptions, but also to assist

students in reconstructing their conceptions so that they become scientifically

acceptable. When assessment is used to assist students in the construction of

knowledge, in other words “assessment for learning and not of learning” (Furtak & Ruiz-

Primo, 2008, p.800), it is known as formative assessment. According to Black and

William, as cited by Furtak and Ruiz-Primo (2008, p.800), formative assessments are

“all those activities undertaken by teachers, and/or by their students, which provide

information to be used as feedback to modify the teaching and learning activities in

which they are engaged.” Formative assessment “monitors and supports the learning

process” (Department of Education, 2003, p.56).

Treagust et al. (2001, p.155) promote the use of formative assessments such as writing

tasks, performance tasks and portfolio-based assessment, because it gives students

“the opportunity to express their understanding and reconcile their personal ideas with

scientifically accepted ideas.” Mintzes et al., (2001) add that the use of concept maps,

written and oral reports and collaborative assessment strategies also support the co-

construction of knowledge in small groups and the reconstruction of individual

misconceptions. The use of a variety of formative assessment strategies by

teachers increases the opportunities they have to attend to students’ conceptions

(Furtak & Ruiz-Primo, 2008).

Shaw et al., (2010) do, however, warn that since formative assessments require

students to express their ideas in greater detail, they may generate additional linguistic

challenges for students. However, formative assessment may be seen as an

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opportunity to develop students’ linguistic ability (Hein, 1999). Treagust et al., (2001)

argue that formative assessments should also not require only very short answers from

students, as short answers do not encourage in-depth thinking. Hence, training teachers

in the formulation of assessments which use open-ended clarifying questions, questions

that expose the students’ understanding, is vital. It is also important not to distort the

purpose of formative assessment by using it to assess the performance of students and

for promoting students to the next grade. Klassen (2006) reminds us that there is not

enough evidence to guarantee the reliability and validity of formative methods for that

purpose. Since teachers, and sometimes peers, co-construct the formative assessment

product in the form of an essay, presentation or concept map, it may not reliably

represent the individual student’s understanding. Therefore, summative assessment

should be used to measure the performance of students as it aims to assess learning

(Department of Education, 2003).

Many new forms of assessment have been introduced, each posing new challenges.

Nevertheless, since assessment remains one of the most important tools for revealing

and remediating student misconceptions, it is vital that we continue to reflect on how we

use assessment to do just that. The purpose of assessment at schools should become

more diverse so that it includes tasks which expose and address misconceptions.

2.5.5 The relationship between context and misconceptions

Context refers to the unique setting or situation of an event (Clough & Driver, 1986). I

will commence this discussion by discussing how the relationship between

misconceptions and contexts may be problematic. Next I will discuss how contexts can

form part of the solution to re-crafting misconceptions.

According to Strike (1983), misconceptions are not formed as a result of students’

observations and experiences; rather it is students’ observations and experiences that

are formed by their misconceptions. Hills (1983) emphasises that “observation is theory-

laden.” In other words, students see what they expect to see. Also, students use their

misconceptions to make sense of what they observe and experience in everyday-life

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situations (Carr et al., 1994). Therefore, misconceptions are seen to apply to

everyday-life contexts.

Strike (1983) explains that misconceptions can actually be valid and functional within

some contexts. It is when misconceptions are extended beyond their productive range

of application that they lead to erroneous conclusions. In other words, misconceptions

have a limited “context of application” (Smith et al., 1993, p.148).

When scientific knowledge does not match students’ misconceptions, students may

create a separate context of application for scientific knowledge, in order to assimilate it.

This separate context of application is usually the situation sketched in exemplar-type

questions used in Physical Sciences classrooms. Gunstone & Watts (1985, p.88)

explain that “It is not uncommon for students to learn the physicists’ perspective and

apply it to identifiably ‘physics-type’ situations, while still interpreting the real world in

other ways.” In other words, scientific knowledge is seen, by students holding

misconceptions, to apply only to the classroom context. As a result,

misconceptions and scientific knowledge co-exist within students’ conceptual

frameworks, each within their own separate context (Klassen, 2006; Tytler, 1998).

The co-existence of misconceptions and scientific knowledge within students’

conceptual frameworks is problematic. Firstly, the new scientific knowledge is only

loosely added on to the student’s conceptual framework and is seen to have a limited

context of application. Secondly, the misconception has a limited context of application.

Thirdly, when students are expected to apply Physical Sciences to an everyday-life

situation, the everyday-life context cues the use of misconceptions and everyday

social language (Duit & Haeussler, 1994; Tytler, 1998). Also, since contemporary

assessments promote the application of knowledge, everyday-life contextual cues are

common. Another dimension of this problem is that sometimes students are unfamiliar

with the everyday-life context used in assessments. If the student has never

experienced the real-life context used in assessment or teaching, then the student will

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struggle to make the connection between the context of application and the scientific

concept under assessment.

The solution, however, is not to terminate the use of everyday-life contextual questions.

Instead teachers need to be aware of these contextual cues and need to focus on

enabling conceptual change. Conceptual change involves re-crafting the

misconception so that it represents the scientific knowledge, thereby broadening

its contextual domain of application (Halloun, 1998). Dekkers and Thijs (1998, p.49)

describe this as “context expansion”, when the context of application of scientific

concepts is extended from the classroom context to the practical context. Palmer (1997)

recommends exposing students to a range of qualitative problems with a variety of

different contextual features in order to expand the student’s range of application.

Another important dimension of the remediation of misconceptions is the classroom

context, or learning environment. Since conceptual change of misconceptions is more

than a cognitive activity, and is influenced by motivational and affective factors such as

discussed in section 2.4.3, the classroom context should support knowledge

refinement and the re-crafting of misconceptions (Smith et al., 1993). In order to

support the refinement and re-crafting of misconceptions, the classroom context must

allow children the freedom to express their ideas without fear of being ridiculed.

2.5.6 Misconceptions within the field of Physics

In this section I will review research studies that have identified common student

misconceptions. In this review I will focus in particular on studies related to Physics

topics that are addressed in the South African Physical Sciences curriculum.

2.5.6.1 Misconceptions regarding Newton’s Laws on Motion

Possibly the most well researched topic in the field of misconceptions is that of

mechanics (Clough & Driver, 1986; Mintzes et al., 1998). Research has shown that

misconceptions on force are very resistant to change (Gunstone & Watts, 1985;

Halloun, 1998). I will continue by discussing cases of misconceptions regarding force.

50

One common misconception is that force is a “primary quality of an object” (Galili in

Moore & Harrison, 2004, p.3) as opposed to an interaction between objects

(Shymansky et al., 1997). This misconception has been described as similar to

medieval impetus theory which attributes motion to an internal source of force or

impetus (Bayraktar, 2009; Gunstone & Watts, 1985). Students holding this

misconception ascribe the incorrect ontological category to force, and see it as a

property of matter, much like mass, instead of seeing it as an interaction between two

objects.

A second common misconception is that “Forces are to do with living things.”

Students holding this misconception attribute human characteristics to an inanimate

object and construct anthropomorphic explanations such as an object “trying to fight its

way upwards against the will of gravity” (Gunstone & Watts, 1985, p.91).

A third common misconception that shares the anthropometric view discussed above is

that during the interaction between two objects “the object with greater mass, or the

more active object, exerts greater force” (Bayraktar, 2009, p.275). Students holding

this misconception view the interaction between objects as a struggle where victory

belongs to the stronger, bigger, heavier, or more active object (Eshach, 2010). This

misconception contradicts Newton’s third law and may be a distortion of Newton’s

second law that indicates that heavier objects require a greater force than lighter objects

to experience the same acceleration.

A fourth common misconception, which may originate from the view that forces are to

do with living things, is that static inanimate objects can’t exert forces (Clement et

al., 1989). Clement explains that although students struggle to believe that a book

exerts a force on the table on which it is lying, many students understand that a

compressed spring is able to exert a force. Teachers can use this to explain that all

objects have a degree of elasticity and are able to exert a force. Students holding this

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misconception also struggle to believe that Newton’s third law applies to the interaction

between a table and a book lying on it (Eshach, 2010).

A fifth common misconception is that if a force is applied to an object it moves

(Dekkers & Thijs, 1998). Students may believe this because it is true in the context of

resultant or unbalanced forces. However, it is incorrect in the context of balanced forces

where the resultant force is zero.

Similar to the fifth common misconception is the sixth common misconception that

objects are at rest or are slowing down in the absence of a force (Gunstone &

Watts, 1985; Mintzes et al., 1998). This is not true, as stationary objects imply a zero

resultant force not the absence of all forces, and slowing down requires a resultant

force.

The seventh common misconception that motion requires a force (Bayraktar, 2009;

Clough & Driver, 1986; Shymansky et al., 1997) is also linked to the previous

misconceptions. This is incorrect because an object can move at a constant velocity in a

frictionless system without the presence of a force. Also, it is more specifically

accelerated motion, which requires a resultant force.

An eighth common misconception is that a force applied to an object causes motion

in the direction of the force (Gunstone & Watts, 1985; Mintzes et al., 1998; Palmer,

1997). This conception is true only in the context where a resultant force is applied to a

stationary object. However, motion can be in a direction opposite to that of the applied

force; for example, when a car’s brakes are applied it continues to move forward for a

considerable distance.

A ninth common misconception is that a constant force causes an object to move at

a constant velocity (Bayraktar, 2009; Mintzes et al., 1998). This misconception

contradicts Newton’s second law which states that a resultant force, which could be

constant or irregular, causes acceleration. Constant resultant forces cause constant

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acceleration and irregular resultant forces cause irregular acceleration. This

misconception is only correct in a context where the constant force is not a resultant

force but rather a balanced force acting on a moving object. An object which

experiences constant applied and frictional forces which are equal in magnitude, in

other words, experiencing a zero resultant force, will move with a constant velocity.

A tenth common misconception is that the rate of motion is proportional to the

magnitude of the force (Mintzes et al., 1998). Students holding this misconception

could either believe that the velocity of an object is proportional to the force or that the

acceleration is proportional to the force. If they believe that the acceleration is

proportional to the force, they are correct if the mass of the object is kept constant and

the force is a resultant force. When comparing the acceleration of objects with equal

masses under the action of a resultant force the rate of acceleration will also be

proportional to the magnitude of the resultant force according to Newton’s second law.

Students who believe that the velocity of an object is proportional to the force, believe

that the slower an object moves the less the force is that is acting on it. This is not

correct, as the velocity of an object does not only depend on the forces acting on it but

also depends on the object’s mass. In addition, the velocity of an object does not only

depend on the applied force acting on it, but also depends on the frictional and braking

forces acting on the object. Objects may move slowly even when a large resultant force

is acting on them, this happens when the large force has only been active for a short

period of time or when the object is very heavy.

An eleventh common misconception is that forces acting on two different objects

can be added (Halloun, 1998). Although it is true that the resultant force acting on each

of two stationary interacting bodies is zero, it is not because the forces they are exerting

on one another add up to zero, but rather because the forces acting on each body

separately add up to zero.

Although the above conceptions are incorrect within certain contexts, they are correct in

others, which is why Dekkers & Thijs (1998, p.41) argue that although these

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conceptions “need refinement” they “have the potential to become the basis for

development of the physics concept of force.”

2.5.6.2 Misconceptions regarding momentum and kinetic energy

The difficulties associated with teaching and learning momentum and kinetic energy has

been discussed in a number of international studies (Bryce & MacMillan, 2009; Lin,

1983). Students struggle with developing an understanding of the difference between

momentum and kinetic energy, and the conservation of these quantities. Students hold

a variety of alternative conceptions regarding momentum and kinetic energy. I will

continue by discussing the common alternative conceptions held by students regarding

the two quantities of motion: momentum and kinetic energy.

One misconception is that momentum and kinetic energy are the same (Bryce &

MacMillan, 2009; Lin, 1983). One of the students in Lin’s study, on the relationship

between Physics students, the Physics classroom and Physics subject material,

explained that momentum and kinetic energy are the same because “They both

incorporate mass and velocity” (Lin, 1983, p.451). These two quantities of mass in

motion appear to be so similar, that even pioneering physicists found the development

of these two concepts to be a difficult and drawn-out task (Bryce & MacMillan, 2009).

Bryce and MacMillan (2009) add that simply pointing out the differences in the

mathematical formulae and emphasising the practice of plugging numbers into these

formulae do nothing to enhance the understanding of students regarding the difference

between momentum and kinetic energy. They suggest that the differences between

these quantities be dealt with more explicitly by discussing how momentum and kinetic

energy are affected by a change in an object’s motion. Since, the resultant force X time

= change in momentum, while the resultant force x distance = work = change in energy,

doubling the velocity of an object will double its momentum and double the time

required to bring it to rest with the same force; whereas as doubling the velocity of an

object will quadruple the kinetic energy (Ek = 1/2mv2) and quadruple the distance

required to stop the object using the same force (Bryce & MacMillan, 2009). According

to Bryce and MacMillan, it is also important for teachers to emphasise that kinetic

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energy can be transformed into other forms of energy, whereas momentum cannot be

converted into other forms.

A second common misconception is that kinetic energy is a vector. Students holding

this misconception believe that since “the work done against gravity is ‘real’ and

therefore positive, work done by gravity is ‘negative’” (Bryce & MacMillan, 2009, p.742).

Also, since work done is the change in kinetic energy, students conceive work and

kinetic energy to be directional. Another reason for this intuitive idea is the previously

mentioned difficulty students have in differentiating between kinetic energy and

momentum. Since momentum is a vector, students conceive of kinetic energy as being

a vector. Bryce & MacMillan (2009, p.744) add that “Youngsters familiar with films such

as ‘‘Armageddon’’ are all too aware that the direction of the asteroid approaching the

Earth, bringing with it sufficient energy to annihilate the planet, makes a world of a

difference!”

A third common misconception is that “momentum was conserved for each object in

a system rather than being conserved by the system of objects as a whole” (Bryce &

MacMillan, 2009, p.742). Students holding this misconception do not understand that

momentum is transferred during a collision, thus when they are told that momentum is

conserved and cannot be transformed into something else they may erroneously

assume that each individual object’s momentum is conserved.

A fourth common misconception is that total momentum is not conserved in

collisions with ‘‘immovable’’ objects (Bryce & MacMillan, 2009, p.742). Students

holding this misconception may think that since the “immovable” object cannot move,

the momentum of the moving object cannot be transferred to the “immovable” object, in

which case the momentum must be lost. This is incorrect as the “immovable” object will

be able to absorb some of the transferred momentum; also the moving object will be

able to keep some of its momentum and continue moving over or around the

“immovable” object. Finally, if there is still any momentum left and the moving object

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transfers this momentum to the “immovable” object, the “immovable” object may move;

any “immovable” object can be forced to move if a great enough force is applied.

A fifth common misconception is that “the size of the force exerted by an object

hitting a surface was related only to the initial velocity of that object, rather than

to its change in velocity and hence its change in momentum” (Bryce & MacMillan,

2009, p.742). Although it is true that a greater initial velocity of an object striking a

surface causes a greater force of interaction, e.g., Fnet = ∆mv/∆t =1(0-10)/1 = -10N

versus Fnet = ∆mv/∆t =1(0-100)/1 = -100N, the initial velocity is not the only variable that

has an effect on the force of interaction. Both the mass of the object and the final

velocity of the object also affect the force of interaction between two objects. The

greater the mass of the object the greater the force of interaction according to the

equation: Fnet = ∆mv/∆t. The smaller the final velocity of the object the greater the force

of interaction, e.g. Fnet = m (v-u) /∆t = 1(5-10)/1 = -5N versus Fnet = m (v-u) /∆t = 1(0-

10)/1 = -10N.

A sixth common misconception is that since total momentum is conserved during a

collision, total kinetic energy is conserved during a collision (Bryce & MacMillan,

2009). Students holding this misconception are once again unclear on the difference

between momentum and kinetic energy, and do not understand that kinetic energy can

be transformed into other forms of energy. Students often rote-learn the rule that kinetic

energy is only conserved in elastic collisions and then get tied up into the circular

argument that inelastic collisions occur when kinetic energy is not conserved and kinetic

energy is not conserved during inelastic collisions, without coming to a real

understanding of what happens during elastic and inelastic collisions. Bryce &

MacMillan (2009, p.755) suggest explaining that:

Contact between two objects during a collision results in vibrations occurring in each. This means

that work is being done internally since the vibration entails movement through a small distance,

a consequence of which is that some of the original kinetic energy is converted into other energy

forms, like heat and sound. On the other hand, if the colliding objects are deemed to be perfectly

rigid, or if they do not make actual physical contact with one another, then these internal

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vibrations do not occur and so no kinetic energy is lost as no internal work is done. Likewise,

where both objects are capable of returning entirely to their original shape after a collision (so-

called ‘‘super’’ rubber balls), it would also be termed elastic. There would be no net displacement

of the material in the balls and so all of the intermediate forms of energy are converted back into

kinetic energy.

Another problem related to the teaching of momentum is that school syllabi often focus

on isolated systems, which causes students to be confused about how the conservation

of total momentum applies to open systems. Teachers need to discuss the fact that the

total momentum in the universe is a constant; when a collision occurs momentum is

transferred not only between the bodies involved in the collision but also between the

colliding bodies and the surface, air and objects inside of the colliding bodies (Bryce &

MacMillan, 2009).

Finally, it would seem that most students are not persuaded about the differences

between momentum and kinetic energy. Teachers need to be granted more time to

discuss and co-construct these complex concepts with their students.

2.5.6.3 Misconceptions regarding the conservation of energy

In this section I will commence by discussing students’ misconceptions regarding the

conservation of energy. I will continue by discussing why these misconceptions are

constructed and how they can be remediated.

Driver and Warrington, as cited by Shymansky et al. (1997, p.575), have found that

“secondary students rarely used conservation of energy principles spontaneously to

analyze problems.” In addition, Shymansky et al. (1997, p.587) found that students

believe that energy is not conserved and that “Motion can create energy; force

creates energy; when you apply a force you use up energy; energy is created

when energy is working.” Duit and Haeussler (1994), Solbes, Guisasola and Tarín

(2009) and Trumper (1998) explain that students often believe that energy is a kind of

fuel or material entity, which may clarify why they think that it can be used up. Clearly

students struggle to understand the conservation of energy (Shipstone in Driver et al.,

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1985) and speak of energy being created and used up or lost. These ideas are incorrect

because the scientific law of conservation of energy states that energy cannot be

created or destroyed, only transferred to other objects, transformed into other forms of

energy, or degraded.

The concept of energy is used often in everyday contexts and in everyday social

language it is normal to make use of phrases such as “I’ve run out of energy” (Scott et

al., 2007, p.49) or ‘‘consumption of energy’’ or ‘‘energy crisis’’ (Solbes et al., 2009,

p.266). Hence, the scientific idea that energy is not used up, appears to be far-fetched

in relation to everyday ways of thinking (Scott et al., 2007) and speaking. This everyday

manner of thinking and speaking about energy being used up or created is often

extended into the classroom environment by teachers, textbook writers and the

producers of audiovisual resources who attempt to simplify the abstract concept of

energy by relating it to everyday experience and social language. The idea that energy

is not conserved is also reinforced by the incorrect use of language that occurs during

the construction of explanations in other fields of Physical Sciences, such as electricity.

Teachers and textbook writers speak of “energy lost in power lines” and “lost volts”,

even speaking of the “generation of electricity” without discussing the transformation of

potential energy to kinetic energy, could leave a student with the idea that energy is

created. In modern times it is not uncommon to hear social media reinforcing the

message that energy needs to be conserved. This may reinforce the misconception that

energy can be used up, especially when students do not understand the transformation,

transport and degradation of energy.

These misconceptions are also strengthened by everyday observations as it is often

difficult to detect the transference or transformation of energy. For example, the energy

that is converted to heat due to friction often dissipates into the surroundings without a

noticeable change in temperature, making it hard to believe that energy was

transformed and that the surrounding particles have more internal energy.

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Another reason for the gap which exists between everyday energy concepts and

scientific energy concepts is the attempt to simplify matters by dealing with isolated

systems, which rarely exist. Students learn that “mechanical energy is conserved in

isolated systems” without a proper understanding of the energy transformation and

transference that takes place in open systems. Hence, when they are asked to relate

their understanding of energy to open systems, they fall back on the idea that energy is

lost.

The remediation of misconceptions regarding the conservation of energy may be

addressed by teaching all four of the “energy quadriga” (Duit & Haeussler, 1994, p.185).

The energy quadriga refers to the following four important aspects of the energy

concept: energy transformation, energy transport, energy conservation and energy

degradation. The degradation aspect of energy is often neglected in school Physical

Sciences, which makes it difficult for students to understand the conservation aspect

(Duit & Haeussler, 1994). The degradation of energy involves the transformation of

energy into useless forms of energy, during interactions and processes. Teaching

students about the degradation of energy may help to remediate misconceptions which

are reinforced by the “apparent contradiction between ‘energy conservation’ and the

‘need for energy resources’” (Solbes et al., 2009, p.267).

2.5.6.4 Misconceptions regarding electricity and electromagnetism

A great deal of research has been devoted to understanding the difficulties that students

experience in learning about electric circuits, (Bull, Jackson & Lancaster, 2010; Cheng

& Shipstone, 2003; Glauert, 2009; Periago & Bohigas, 2005; Pilatou & Stavridou, 2004;

Shepardson & Moje, 1999; Steinberg, 1983; Woods, 1994). According to (Mulhall,

McKittrick & Gunstone, 2001) the concepts related to electricity are particularly

problematic due to their highly abstract and complex nature. I will continue this

discussion by listing some of the misconceptions recorded in previous research:

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• Electrical potential, potential difference, emf, and voltage are the same

thing (Cheng & Shipstone, 2003; Shipstone in Driver et al., 1985; Steinberg,

1983);

• Electrons carry positive charge (Bull et al., 2010);

• Potential difference is caused by current flow (Bull et al., 2010; Mulhall et al.,

2001; Shipstone in Driver et al., 1985; Steinberg, 1983);

• Voltage and current are the same (Bull et al., 2010; Shipstone in Driver et al.,

1985);

• Voltage across parallel branches is different for each branch (Bull et al.,

2010);

• Current can change within a branch (Bull et al., 2010);

• Current gets used up (Shipstone in Driver et al., 1985; Steinberg, 1983).

Research also shows that students tend to focus on what happens at only one point in a

circuit and forget that they are dealing with a multifaceted interrelated system (Cheng &

Shipstone, 2003; Steinberg, 1983). This localised reasoning makes solving circuit

problems problematic.

2.5.7 Strategies for the identification and reconstruction of misconceptions

Earlier in this chapter I have discussed the importance of teachers being aware of their

students’ prior knowledge and alternative conceptions. Pine et al. (2001, p.93) remind

us that: “If teachers are better informed about the types of false beliefs children are

likely to hold they will be quicker and better at identifying them, at helping children call

them to mind and make them explicit and at incorporating them into the process of

conceptual change.” In addition, students also need to be aware of their own alternative

conceptions, and how these conceptions relate to new conceptions they are studying.

Beeth and Hewson (1998, p.754) point out that “The important role of metacognition

and reflection in the development of autonomous students is widely acknowledged in

the educational literature.”

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Remediation or reconstruction of student misconceptions may, however, involve more

than mere student and teacher awareness. Tyson, Treagust and Bucat as quoted by

Canpolat (2006, p.1758) warn that bringing misconceptions to the attention of students

does not mean that they will change their conceptions. As these conceptions are

extremely resistant to change, teachers need to make use of alternative teaching

strategies that make use of student conceptions in the process of developing new

conceptions. Such alternative teaching strategies are discussed in the subsequent

sections.

2.5.7.1 Concept maps

Concept maps are a type of graphic organiser that can be used to represent the

relationships among concepts (İngeç, 2009). Trowbridge and Wandersee (1998, p.116)

describe concept maps as a hierarchy of concepts with a “superordinate concept at the

top”. The relationships between concepts are indicated by labelled lines. Teachers can

use concept mapping as a strategy to develop student conceptions by firstly guiding

students through the process of constructing a concept map and then by giving them

the opportunity to construct their own concept maps at the start of a new content area.

These concept maps can then be used by teachers to identify students’ preconceptions

and further inform the teaching process. According to Trowbridge and Wandersee

(1998, p.123)

Various aspects of a student constructed map may reveal alternative conceptions. The presence

of incorrect linkages forming invalid propositions is one indicator. The incorporation of concepts

not related to the superordinate concept or concepts that seem trite or irrelevant is another

indicator. … Missing concepts further indicate a student’s lack of understanding.

Since concept maps are intended to represent the “cognitive networks that have been

constructed by students in the process of learning” (Klassen, 2006, p.834) they can be

modified by the students throughout the learning process in order to allow for both

reflection on, and the extension of, the student’s understanding (Mintzes et al., 1998).

Unfortunately, the use of concept maps remains an uncommon practice in most

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Physical Sciences classrooms, largely due to the time constraints enforced by an

extensive curriculum.

2.5.7.2 Writing activities

The use of writing activities is another teaching strategy which can be used to develop

students’ alternative conceptions (Treagust et al., 2001); however, it too is not common

practice in Physical Sciences classrooms (Ruiz-Primo, Tsai & Schneider, 2010). Furtak

and Ruiz-Primo (2008) explain that writing activities are a more tangible way of

obtaining students’ conceptions. However, the use of writing activities requires practice

and is time-consuming as it requires students to express their understanding and to

think more deeply about why they believe what they do. Teachers also view the time

required to read and evaluate written products as excessive (Furtak & Ruiz-Primo,

2008; Mintzes et al., 2001). Hein (1999) suggests staggering writing assignments so as

to allow for enough time to present each class with valuable feedback. Another reason

for the limited use of explanation-type questions and writing activities is the over-

emphasis on numerical questioning in assessment. Also, many students do not have

the linguistic ability to cope with writing activities (Unsworth, 2001). On the other hand,

Hein (1999, p.140) explains that writing activities help to enhance students’

communication skills “whether English is their first language or not”.

Writing activities do not only have the potential to enhance the linguistic ability of

students, as mentioned previously they can also be used to help students organise their

thoughts (Treagust et al., 2001). According to Carlsen (2007) writing activities improve

students’ constructions of scientific concepts and help students to link new ideas with

prior knowledge. Since misconceptions form part of students’ prior knowledge, writing

activities can be used to help students’ link new ideas to their misconceptions and to

reconstruct their misconceptions. Unsworth (2001, p.586) argues that “developing

students’ knowledge and understanding in school science, and developing their

knowledge of the language forms that construct and communicate that understanding,

is one and the same thing.” Hein (1999,137) adds that writing “can be an effective

vehicle for allowing students to develop their critical thinking and problem-solving skills,

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as well as deal with their personal misconceptions regarding a specific topic in physics.”

Emig, cited by Grimberg and Hand (2009, p.504), argues that “because writing is often

our representation of the world made visible, embodying process and product, writing is

more readily a form and source of learning than talking.”

Teachers can use a variety of writing activities to diagnose and remediate

misconceptions. These include the writing of folder activities by students (Hein, 1999),

and Science Writing Heuristic (SWH) activities (Akkus, Gunel & Hand, 2007; Grimberg

& Hand, 2009; Hand, 2004). Hein (1999) describes her folder activities as a collection of

writing activities completed by a student and stored in a separate folder. These activities

require students to explain a problem or a concept, which was highlighted or discussed

during a class session, in their own words and with enough detail so that someone who

did not attend the class would be able to understand their explanation. These folder

activities should then be used to diagnose misconceptions and to plan teaching

activities which address the remediation of these misconceptions, rather than for the

purpose of grading or promotion. Akkus et al. (2007, p.1748) describe the SWH

activities as a different option to the conventional laboratory report, instead of

completing the aim, method, observations, results, and conclusion, students are

expected to complete sections on: “questioning, knowledge claims, evidence,

description of data and observations, methods, reflection on changes to their own

thinking.” By reflecting on changes to their own thinking, students are encouraged to link

new information to their preconceptions and to reconstruct their misconceptions. Thus, it

is evident that writing activities are an important teaching strategy, also with regard to

the remediation of misconceptions.

2.5.7.3 Group discussions and debates

Writing activities are not the only language-based activities which promote the

remediation of misconceptions. According to Rivard, cited by Akkus et al., (2007),

students’ understanding is enhanced when they are involved in verbal explanation

activities. Research has shown that students who verbalise their understanding are

more successful in conceptual development than students who do not verbalise their

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understanding (Jones & Carter, 1998). Carr et al. (1994) explain that students can

change their misconceptions when allowed to engage in conversation within a safe

environment. There are a variety of discussion activities which can be used to develop

conceptual understanding amongst students; in this section I will first discuss the use of

group discussions and then the use of debate in the Physical Sciences classroom.

In order for students to reconstruct their misconceptions they need to actively participate

in the learning process, hence Mintzes et al. (1998) encourage the use of activities such

as cooperative group work and debates. Jones and Carter (1998) explain that peer-peer

discussion helps students to interpret new knowledge and advances the development of

complex conceptions during the exchange of ideas. In order to maximise the conceptual

development of students during group work it is important to create a healthy learning

environment where students respect one another’s opinions and are not afraid to share

their understanding (Vosniadou, & Ioannides, 1998), or misunderstanding. Jones and

Carter (1998, p.273) also advise that the size of the groups will influence the type of

experience that the students will have; weak students should not be grouped together

as the construction process stops when no one in the group has the necessary

capability. In addition, Jones and Carter explain that each member should receive

cognitive roles such as “executive, sceptic, educator, and record keeper” to encourage

active participation of all group members.

The use of open debate in the Physical Sciences class allows students the opportunity

to explain their understanding, while coming to an understanding of how their

conceptions differ from the conceptions of other students (Nussbaum, 1998), and how

their misconceptions may be revised. Berland and Reiser (2008) argue that when

students are engaged in debate they are required to do more than merely explain their

understanding, they are expected to persuade others and to defend their

understandings. This often requires a change in the beliefs that teachers and students

hold concerning the nature of scientific knowledge and the process of learning, as they

are required to view Physical Sciences as “building knowledge with peers” (Berland &

Reiser, 2008, p.50). Nevertheless, investing time in student’ debate and group

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discussions promises enhanced conceptual understanding and the opportunity to

reconstruct misconceptions.

2.5.7.4 Practical investigations

Students’ understandings and misconceptions evolve as a result of the interaction

between their prior understanding and experience. Hence it is important for teachers to

provide students with experiences such as practical experiments which have the

potential to enhance their understanding and remediate their misconceptions. Ausubel

(in Novak, 2004, p.32), maintains that “students require concrete-empirical props to

develop abstract concepts.”

Vosniadou and Ioannides (1998) warn that teachers need to be careful to choose

experiments that will provide the cognitive dissonance necessary for conceptual

change, otherwise students may observe only those features which support their

misconceptions (Pine et al., 2001). In addition, it is important to make use of “open-

ended investigations that devolve as many decisions as possible to the students”

(Moore & Harrison, 2004, p.1), as opposed to the “closed work” type (Simon & Jones,

cited by Gilbert et al. 1998b, p.194) where the aim, method, method of data analysis,

even the results, are prescribed by the teacher. Otherwise, practical activities may

become just as meaningless to students as rote learning and recipe-type calculations

and just as ineffective in the remediation of misconceptions; especially when students

do not have the skills and understanding required to process their observations (Novak,

2004). Campanario (2002, p.1097), warns that students often draw incorrect

conclusions during practical activities and that “the experience, contrary to expectations,

does not guarantee change of conception by itself.” In addition, Hart, Mulhall, Berry,

Loughran and Gunstone (2000) add that research has shown that experimentation does

little to promote meaningful learning, due to factors such as the cognitive overload of

students, a lack of understanding of the purposes involved during experimentation and

the fact that students’ observations differ from what is expected due to their differing

conceptual frameworks. Hence, it may be necessary to enhance practical

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investigations. I will continue this discussion by highlighting three contemporary

teaching strategies designed to improve practical investigation.

Predict-Observe-Explain (POE) is a teaching strategy where students are shown an

authentic situation and are then asked to give their prediction about how a specific

change to the situation will affect the situation. Next they get to observe the changes

and write down their observations. Lastly, the students attempt to reconcile their

predictions and observations (Gunstone & Mitchell, 1998). POEs can be used to elicit

students’ ideas and misconceptions; they can also be used to enhance student

understanding and remediate misconceptions at various stages during the teaching of a

specific content area (Furtak & Ruiz-Primo, 2008).

Science Writing Heuristic (SWH) activities, as discussed in the previous section, can

also be used to enhance traditional practical investigations. SWH activities are a more

effective manner of writing the report on a practical investigation; it allows students to

reflect on changes in their understanding and to reconstruct their ideas on paper.

Another type of experiment which can be used to remediate misconceptions is the

thought experiment. Thought experiments are “a way of exploring the logical

consequences of a set of ideas in various idealized situations, including imagining what

happens when the effects of a variable become extremely small or are entirely

eliminated” (Smith, 2007, p.355). Thought experiments can be used to allow students

the opportunity to explain and develop their ideas.

2.6 CONCLUSION

At the beginning of this chapter I defined the key concepts of this study. In searching for

the definitions of misconceptions, pre-knowledge and explanations, I found them to be

complex concepts that have elicited a variety of different opinions and theories with

regard to their meanings. I came to the conclusion that misconceptions are alternative

conceptions that form part of students' pre-knowledge and that these conceptions are

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under construction and form useful anchors for the accommodation of new information.

Pre-knowledge is the students’ conceptual framework as it exists prior to formal

education events. Pre-knowledge is important because new knowledge must be linked

and re-crafted into students’ pre-knowledge. Explanations are also an important part of

learning. They are descriptions and rationalisations of students’ understandings which

can be used for the diagnosis of misconceptions. However, explanations are also

learning tools, because knowledge is constructed and misconceptions can be re-crafted

during the formulation of explanations.

After defining the key concepts of this study I went on to discuss the theories which form

the theoretical and conceptual framework of my study. According to the theory of

constructivism knowledge is not merely transferred from the teacher to the student, it is

interpreted in terms of the student’s pre-knowledge and constructed by the student.

Hence, misconceptions cannot be removed and replaced by teaching the student the

correct conceptions. Instead, teachers need to be aware of misconceptions, so that they

can support students in the re-crafting of these misconceptions. According to the theory

of social constructivism teachers can influence the construction and re-crafting of

knowledge, because knowledge is seen to be constructed socially by the student and

various social role players and factors. In addition, teachers and other social role

players and social factors, such as students’ peers, family, media, textbooks and

classroom environment, may also have a negative effect on learning in terms of

providing information which could be crafted into a misconception. In order for teachers

to support the re-crafting of student’ misconceptions they need to diagnose these

misconceptions. Students’ explanations can provide valuable information with regard to

the misconceptions they hold. In this study, I used Dagher and Cossman’s conceptual

framework of explanation-types to classify explanations and to gain information

regarding the student misconceptions revealed in these explanations.

Next I discussed the nature of misconceptions which can either be seen as stumbling

blocks which hinder learning, or as building blocks with which new knowledge is

constructed. I continued by discussing the complex process of conceptual change which

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is a gradual process of re-crafting pre-knowledge, including misconceptions. I also

discussed the various sources of misconceptions from the individual to various other

social role-players and social factors. I reviewed studies on the relationship between

misconceptions and language, assessment and context. I found that language,

assessment and context can be useful in diagnosing misconceptions, but may also

hinder the diagnosis of misconceptions. Furthermore, I found that language;

assessment and context may be used to remediate misconceptions, but may also

reinforce misconceptions. I went on to identify specific student misconceptions in the

field of Physics, and discussed contemporary teaching strategies that can be used to

remediate misconceptions.

In the next chapter I will discuss the method that I used to collect data on the

misconceptions held by a sample of grade 12 Physical Sciences students.

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CHAPTER 3

RESEARCH DESIGN AND METHODOLOGY

3.1 INTRODUCTION

In this chapter I will discuss the selection of an appropriate research design genre and

research methodology for this study. According to Mouton (2001), the research design

genre can be associated with the architectural plans for a house, and the research

methodology with the construction process. Mouton (2009) also emphasises that a

research framework should not start at the design and method, but rather with an

outline of the researcher’s beliefs of what knowledge is, that is, an epistemology. In

other words, just as one needs to reflect on your beliefs regarding what a house should

be, in order to select a suitable plan; researchers need to reflect on their beliefs

regarding knowledge, in order to select a suitable design genre. It is also important for

researchers to behave ethically as they reflect on their epistemology, select a research

genre and construct suitable evidence. I will discuss the ethical considerations related to

this study in this chapter.

Mouton’s (2009) metaphorical comparison of the construction of a house with the

construction of a research study suits this study because it is framed in the theories of

constructivism and social constructivism. Therefore, the structure of this chapter will

continue along the lines of the construction metaphor. I will commence by describing the

structure to be constructed – the evidence for the research questions. Then I will

discuss my beliefs regarding the knowledge to be constructed – epistemology, the

research plan for the construction process – research genre, the construction process –

research methodology, the collection of construction materials – data collection, the

construction of evidence – data analysis and, lastly, the cleaning up of the construction

site – data storage.

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3.2 THE STRUCTURE TO BE CONSTRUCTED – RESEARCH QUESTIONS

The poor performance of students during the 2008 NSC Physics examination generated

the need to construct an understanding of the common misconceptions held by Physical

Sciences students. Part of the understanding that needs to be constructed also includes

knowledge regarding the performance of students in explanation-type questions, the

types of student explanations that reveal misconceptions and what explanation-types

reveal about student misconceptions. More specifically, answers to the following

research questions need to be constructed:

1. What are the common student misconceptions that are revealed in a high stakes

Physics examination?

2. How do students perform in explanation-type questions?

3. What do explanation-types reveal about student misconceptions?

3.3 BELIEFS REGARDING THE KNOWLEDGE TO BE CONSTRUCTED –

EPISTEMOLOGY

The theoretical framework for this study is the constructivist learning theory social

constructivism. Constructivism is the theory that “knowledge is not transmitted directly

from one knower to another but is actively built up by the student” (Driver et al., as

quoted by Nola in Matthews, 1998, p.56). Social constructivism emphasises the idea

that students do not construct knowledge individually, but rather through social

interactions (Vygotsky, 1978). By selecting social constructivism as the epistemology

which frames this study, my perspective regarding what a misconception is differs from

a positivist’s perspective. From my social constructivist perspective misconceptions are

co-constructed by students together with other social role-players and are not merely

incorrect conceptions which can be remediated by transference of the correct

conception.

The epistemology of social constructivism also influences my choice of research genre,

as the research genre needs to generate evidence matching the belief that

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misconceptions are a social construct. According to Mouton (2009), the researcher

needs to consider what type of evidence constitutes suitable evidence with regard to the

research questions when selecting a research genre. Mouton introduces three modes of

reasoning with regard to the type of evidence, which he call research logics. I will

continue by rationalising about what type of evidence is suitable for this study, by using

Mouton’s research logics as a guideline.

Mouton’s first pair of research logics is the logics of contextualisation and

generalisation. The logic of contextualisation as opposed to the logic of generalisation

involves the in-depth investigation of a case or small number of cases. My study is

conducted within the logic of contextualisation, because the students’

misconceptions, as evident in a sample of answer scripts, have inherent value and need

not be representative of the larger population. The fact that these misconceptions may

not be held by most students, and hence cannot be generalised, does not take away

from the importance of teachers becoming more aware of possible misconceptions and

their relation to student explanations. Knowing more about students’ misconceptions will

assist teachers in being better prepared to adapt their teaching strategies.

Mouton’s second pair of research logics is the logics of discovery and validation. The

logic of discovery within research implies that the research generates new hypotheses

and frameworks as opposed to the logic of validation which tests existing hypotheses

and frameworks. My study involves the logic of discovery as I planned to ascertain

common misconceptions and their relation to student explanations, instead of testing a

hypothesis regarding student misconceptions.

Mouton’s third pair of research logics is the logics of synchronicity and diachronicity.

The final logic or reasoning underlying my study is the logic of synchronicity.

Synchronicity refers to the examination of a situation over a period of time, whereas

diachronicity refers to examination of a situation at a given point in time. Although my

study focused on the 2008 matric examination, the misconceptions evidenced in the

exam scripts were constructed and re-constructed gradually over a period of time. In

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this study I not only aimed to find out what misconceptions students hold, but to find out

more about the process through which these misconceptions were constructed and how

they influenced the explanations that students construct.

3.4 RESEARCH PLAN FOR THE CONSTRUCTION OF KNOWLEDGE –

RESEARCH GENRE

The nature of the data required for this study informed the selection of a suitable

research genre. The data required were detailed descriptions of what misconceptions a

specific group of students hold and what their explanations expose about the nature of

these misconceptions. The context to be investigated was the performance of grade 12

students during the NSC examination of 2008. The exam scripts of these students had

been made available for research and they contained a great deal of information on

what students understand and the misconceptions they hold. An analysis of the textual

content in the students’ exam scripts would yield the data required. The analysis of

content in any form of communication is known as content analysis (Breecher et al.,

1993). According to Kaplan (1943, p.230) content analysis “attempts to characterise the

meanings in a given body of discourse in a systematic and quantitative fashion.”

Krippendorff (2004, p.18) explains that content analysis is a “research technique for

making replicable and valid inferences from texts (or other meaningful matter) to the

contexts of their use.” The methodology of content analysis involves the exploration of

communications in order to gain an answer to the research question (Thomas, 2003).

Characterising and describing the meaning of student explanations from their exam-

script responses would yield suitable data regarding their misconceptions, therefore

content analysis was selected as the suitable research genre for this study.

Early definitions of content analysis specified the quantification of data (Kaplan, 1943).

Textual data can be quantified by counting the occurrence of specific words or themes

(Franzosi, n.d.). The identification and classification of specific words or themes is

known as coding. Coding the exam-script responses in this study would be useful.

Specific codes could be allocated to certain misconceptions and explanations and then

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these codes could be counted in order to determine the frequency of student

misconceptions and explanation-types.

An indication of the frequency of misconceptions revealed in the 2008 exam scripts

would serve as an interesting introduction to this study. However, the aim is to construct

a deeper understanding of student misconceptions. In other words, the focus is not so

much on the quantification of the data, but rather on the qualitative description of the

data. Content analysis occurs in many forms, and later definitions indicate that

quantification need not be the only focus of such an analysis (Krippendorf, 2004).

According to Shaw (2006) “The perspective which views content analysis as a purely

quantitative method fails to recognize the degree to which interpretation of texts

underlies the development of a coding scheme.” Franzosi (n.d., p.189) argues that “To

think in terms of a quantitative versus a qualitative approach to texts is a misguided

approach. Each has strengths and weaknesses.” The best approach is probably a

combination of counting common themes and regularly delving deeper into the meaning

of those themes.

The second phase of this study involves the collection and analysis of interview data

with the purpose of further clarifying the nature of student explanations and

misconceptions. White and Marsh (2006) explain that content analysis has been used to

analyse interview transcripts. They emphasise that the most important criteria for

selecting data for a content analysis is the value of the data with regard to supplying

valuable evidence for answering research questions. Since both the exam script and

interview data contain valuable information regarding student misconceptions, I planned

to conduct a content analysis of both of these sets of related communication.

3.5 CONSTRUCTION PROCESS – RESEARCH METHODOLOGY

In order to construct evidence for this study a suitable methodology needs to be

selected. The methodology that best fits my content analysis is a qualitative

methodology that allows me as the researcher to position myself inside the social world

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(Denzin & Lincoln, 2000) as a co-constructor of meaning. My goal is similar to that

which Bogdan and Biklen (1998, p.38) refer to in stating that “The qualitative

researchers’ goal is to better understand human behaviour and experience. They seek

to grasp the processes by which people construct meaning and to describe what those

meanings are.” Franco and Taber (2009, p.1929) explain that a qualitative research

technique is chosen because of the “desire to investigate student thinking in depth” and

“for fine grained exploration of students’ ideas.”

Even though my research will take the form of a qualitative study, I will collect both

numeric and textual data in order to induce or construct a description of student

misconceptions, explanation-types and the relationship between student explanations

and misconceptions.

3.6 COLLECTING MATERIALS – DATA COLLECTION

Since the aims of this study are to identify common misconceptions as evidenced by the

2008 NSC Physics examination and classify them according to the explanations offered

by the students, my primary source of data was a sample of student exam scripts.

However, Schuster (1983) argues that one cannot deduce anything concerning

students’ misconceptions without probing their way of thinking. Therefore, I decided to

interview a sample of students in order to probe their thinking to enable me to construct

a richer description of the misconceptions found in the student exam scripts. I also

included teachers in the interview sample, as they are co-constructors of the knowledge

that their students construct, and I was also interested to find out to what degree they

are aware of the misconceptions held by their students.

In this section, I will discuss the processes of identifying misconceptions and collecting

data from both the student exam scripts and the interviews. I will also discuss the

various ethical considerations that formed part of this study.

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3.6.1 Exam-script data

A total of 218 156 grade 12 students, 17-18 years of age, wrote the 2008 NSC Physics

examination (Appendix H). A random sample of 921 Physics examination scripts was

provided to the University of Johannesburg (UJ) as part of a script analysis project that

was commisioned by the DOE. These were scripts that had already been marked by

external examiners appointed by the DOE. The sample was selected randomly from the

population of students who wrote the 2008 NSC Physical Sciences examinations in

Gauteng. The sample of 921 scripts comprises 0, 4% of the total population of 2008

grade 12 Physical Sciences students. Although this is a small percentage of the total

population, the sample has inherent value and allows for a more in-depth analysis of

student misconceptions.

3.6.2 Interview data

I decided to probe the misconceptions identified in the exam scripts in a second phase

of the study. The second phase of this study involves interviewing students and

teachers. In this section I will discuss the rationale for using interviews and the process

that I followed to collect data from the interviews

3.6.2.1 The rationale behind using interviews to supplement the exam-script

data

I decided to supplement the exam-script data with interview data for two reasons.

Firstly, the interviews would allow me to probe students’ thinking with regard to their

misconceptions. According to Schuster (1983), one needs to explore students’ thinking

in order to illuminate students’ misconceptions. Also, qualitative interviewing

endeavours to illuminate the interviewee’s ideas (Kvale, 1996). Secondly, the use of

both exam-script data and interview data would enhance the validity of this study.

Burton, Brundrett and Jones (2008) and Creswell (2003) explain that the use of multiple

sources of data, which is known as the triangulation of data, helps to ensure the

credibility or validity of research data. Research findings are valid when the research

instruments measure what they claim to measure (Conrad & Serlin, 2006) and when the

findings make sense to the group of people reading the study (Miles & Huberman,

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1994). Although the addition of interview data enhanced the validity of this study it was

not the only method employed to improve the validity. I validated my inquiry further by

applying the methods proposed by Henning et al. (2004) that is: continually checking,

questioning and interpreting my findings; aligning my research methods with my

research question; communicating information regarding the research process and

findings with the research participants and other stakeholders; and ensuring a degree of

“pragmatic validity” by making my findings available for use by the research participants.

I discuss the follow-up communication with the research participants in section 3.6.2.9.

3.6.2.2 Surveying the site

According to Henning et al. (2004, p.143) “surveying the site and gaining entry” are the

steps that follow pre-research activities in the design process. I did not have access to

interview the students whose exam scripts were analysed, because the NSC is an exit

examination. I therefore sought a sample of students from another location, so that I

could probe them on the common misconceptions prevalent from the exam-script

analysis. I decided to conduct the interviews with a later cohort of students to the one

which had written the high stakes national examination. The site which I chose for

conducting the interviews is a high school that is conveniently located. The high school

is an English medium, multicultural and urban school.

3.6.2.3 Gaining entry and acquiring permission — ethical concerns

In order to gain entry and permission to conduct research at the selected high school, I

wrote a letter to the head office and relevant district office of the Gauteng Department of

Education (GDE). I informed them of my study and its’ aims and requested permission

to conduct my research. The letters from the GDE granting permission are included as

appendix B – C.

After receiving permission from the GDE, I wrote letters to the school principal, teachers

and parents requesting written consent to conduct the research and a letter to the

students requesting their assent to participate in the research (appendix D – G).

According to Henning et al. (2004) it is important that consent is informed, so I included

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information regarding the background and purpose of my study as well as information

about the nature and duration of the pre-interview test and interviews. The following

ethical considerations as described by Greene and Hogan (2005, p.81) were also

explained to the principal, teachers, parents and students and adhered to during the

research:

1. Welfare

The students were informed that the research may assist them in identifying

misconceptions which they may have regarding Physics. They would receive

feedback regarding common misconceptions as well as the correct answers for

the explanation-type questions extracted from the 2008 NSC Physics

examination.

2. Protection

The students were informed that the worksheets would not be used by the school

for any form of assessment and that they would not be required to study anything

beforehand.

3. Provision

The students were informed that their participation may contribute to enhancing

teacher awareness of student misconceptions in the field of Physics.

4. Choice and participation

The students were informed that they have the freedom to either agree to or

refuse participation, with the choice to withdraw from the study with impunity.

They were also assured that their identity and responses would be kept

confidential.

After gaining written permission from the GDE and research participants to conduct the

pre-interview test and interviews, I submitted the letters of consent, together with my

research proposal, to UJ and received ethical clearance.

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3.6.2.4 Pre-interview testing for the purposive sampling of interview

participants

I selected a high school to participate in this study as a convenience sample. However, I

needed to find students who held the same misconceptions as those revealed in the

exam-script analysis which took place prior to the selection of the interviewees.

Selecting participants who can best illuminate a specific research problem is known as

purposive sampling (Henning et al., 2004).

In order to select those students who held the same common misconceptions as

identified in the exam-script data, I compiled a pre-interview test. The pre-interview test

consists of the same 12 explanation-type questions used in the exam-script

classification. The pre-interview test (Appendix J) was compiled in a worksheet format

so that students might find it less stressful. A few different versions of the worksheet

were copied, each version differing only in the order in which the questions were asked.

I did this so that if students did not finish the worksheet, or lost concentration, I would

still have enough data on each different question.

The 18 grade 12 Physical Sciences students at the selected school wrote the pre-

interview test shortly before their preliminary examinations; hence they had already

worked through all of the subject content that was included in the pre-interview test. The

students wrote the pre-interview test under the supervision of their teacher and I marked

the tests according to the DOE memorandum (appendix I). After marking the tests I

analysed the tests in order to identify students who had constructed similar

misconceptions as those that were most prevalent in the exam-script sample. I

discerned 10 students who displayed similar misconceptions to those from the exam-

script classification. These 10 students formed the student interview sample.

The similarities between the student interview sample and the exam-script sample are

that they are both a multi-cultural group with a majority of Africans, they include both

male and female students, they include students with a range of academic ability and

they both studied the same curriculum. A difference between the student interview

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sample and the exam-script sample is that the average language ability of the interview

sample, as observed in the pre-interview test, was better than that of the exam-script

sample. However, the misconceptions that were identified in the exam scripts were

identified in scripts where the language ability of the students was average. Very few

misconceptions could be identified in exam-scripts where the language was very poor.

In other words, students which had clearly contructed misconceptions in the exam

scripts used similar language to the students in the interview sample. The socio-

economic backgrounds of the students in the interview sample and the students in the

exam-script sample also differed. The students in the interview sample attended an

urban school with slightly higher than average school fees and with better resources

than most rural schools. On the other hand the students in the exam-script sample

came from either urban, township or rural schools. Despite the differences between the

students in the interview sample and the students in the exam-script sample I found

evidence of similar misconceptions in both samples, thereby verifying that

misconceptions are shared amongst a diversity of cultures, abilities and genders (Alzate

& Puig, 2007; Driver et al., 1985; Mintzes, et al., 1998; Scott et al., 2007; Vosniadou &

Ioannides, 1998).

I planned to include teachers in the interview sample in order to enquire about the

extent to which they are aware of the misconceptions held by their students, the

possible sources of misconceptions and the strategies they are using to address these

misconceptions. The school I had selected had only one grade 12 Physical Sciences

teacher. I decided to interview her as she would have useful information regarding the

misconceptions held by her students from a teachers’ point of view. Since the grade 12

Physical Sciences teacher had only been teaching for a few years, I decided to include

her head of department in the teacher interview sample. The head of the Sciences

department had been teaching Physical Sciences for many years and it was expected

she would have knowledge on students’ misconceptions. I decided that interviewing two

teachers and 10 students would provide sufficient data to help clarify the exam-script

data.

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3.6.2.5 Choosing discursive interviews as the research tool

I chose to conduct discursively oriented interviews as opposed to standardised

interviews, because it would better match the design of this study. According to Warren

(2001, p.83), “the epistemology of the qualitative interview tends to be more

constructionist than positivist.” In discursively oriented interviews, data or information is

co-constructed through the interview process by both the interviewee and interviewer.

Whereas in standardised interviews, facts are merely collected from the interviewees

(Warren, 2001). Henning et al. (2004) argue that the interview- interaction and

discourse influences the data, no matter how neutral the interviewer attempts to be. In

the discursively oriented interview, the data are constructed by the interaction and

characteristics of the interaction, such as trust, ability to express oneself, methods of

expression, class and status differences, social identity, culture and the perspectives of

both the interviewer (reflected in the design of the interview questions) and the

interviewee. Although the researcher has the responsibility of taking control, the

discursively oriented interview places the researcher and the participants in more

equitable roles. According to Glesne in Falk and Blumenreich (2005), it is the

interviewee’s responsibility to make deeper meaning of the students’ experiences.

A standardised interview would yield more superficial information because the students’

responses may be constrained due to the unnatural interaction of the interview and the

limiting structure of the research questions. Discursively oriented interviews allow the

researcher to probe the students’ responses, thus enabling richer data construction.

When given a limited answer, I asked the participants to tell me more about their ideas,

why they held those ideas and/or where they got the ideas from, instead of rigidly

adhering to the pre-set questions. Southerland, Smith and Cummins (2000, pp.91-92),

explain that:

Interviews can provide valuable insights into a student’s meaning. Because the

teacher/researcher’s interpretations are grounded in the student’s voice, we may more fully

understand what a student knows and how she can apply that knowledge. Such thick descriptions

of several students’ conceptual frameworks in a classroom are invaluable tools in planning

classroom instruction.

80

3.6.2.6 Planning the interviews

Despite having the freedom to deviate from pre-set questions in order to move with the

interviewee’s train of thought, it was important to carefully prepare a framework of pre-

set questions, so that I could get the interviewee thinking along the right track. In order

to prepare probing questions, I studied each student’s responses to the pre-interview

test. I then compiled a separate set of questions for each student, specifically probing

those responses which resembled the common misconceptions found in the exam-

script data. Two examples of the probing questions that formed part of my interview

schedule are: “Why do you think that cars with a greater mass exert a greater force on

lighter cars during a collision?” and “Where do you think you got the idea that heavier

cars exert a greater force on lighter cars during a collision?”

I also set interview questions for the two teacher interviewees as part of the interview

schedule. The questions that I used for both the students and teachers were open-

ended questions, questions requesting individual thoughts, experiences and opinions.

One example of an open-ended question which formed part of my interview schedule is:

“From your point of view, what would you say are the main sources of student’

misconceptions?” Before setting out to use the interview schedule of questions

(appendix M), I gave them to my supervisor for his input.

Next I asked the teachers which time would be most suitable for both their interviews

and the students’ interviews. I wanted to ensure that students did not lose any teaching

time, so I asked if the afternoons would be suitable. The teachers explained that since

the students were writing exams they would prefer to be interviewed during the long

waiting periods that they had in between practical exams. Together with the teachers

we set up an interview timetable and I arranged with the school’s librarian to conduct

the interviews in a quiet room attached to the library. Prior to each interview, consent

was requested from each student interviewee, teacher interviewee and from the head of

department to tape-record the conversation. I explained that this was necessary in order

to transcribe the interviews.

81

3.6.2.7 Interview procedure

The students and teachers were interviewed individually. According to Henning et al.

(2004, p.75), interviews share a “typical flow”. I conducted my interviews according to

the “typical flow” described by Henning et al., I discuss this flow next:

1. Scene-setting

At the start of each interview I warmly greeted the interviewee and made him or her

feel as comfortable as possible. I explained to both the students and their teachers

that sharing their experiences, ideas and opinions would be valuable in assisting

both me and them to better understand students’ ideas so that we may help them. I

also briefed them on the course that the interview would take. I explained to the

students that I would be asking them a few questions about the ideas they

expressed in their pre-interview test. I explained to the teachers that I would be

asking them about their experiences and opinions regarding student misconceptions

in Physical Sciences.

2. Providing the interviewee with a set of pre-set questions to scan

Henning et al. explain that this step is not compulsory as it may cause the

interviewee to anticipate certain responses thereby limiting the conversation. As a

result, I excluded this step.

3. Questions and answers

Next, I probed students on their misconceptions. I ask them to explain the reasoning

behind their answers to the questions in the pre-interview test. I asked questions

like: “Why do you think that cars with a greater mass exert a greater force on lighter

cars during a collision?” I also asked the teachers about their experience of

students’ misconceptions, the strategies that they used in an attempt to remediate

misconceptions and their opinion on possible causes of misconceptions. I listened

carefully to both the students and teachers, keeping eye contact and allowing for

pauses. When interviewees did not provide enough information I asked them to

elaborate on what they had said. When their response deviated from what I had

82

prepared, but remained relevant to the study, I asked them to explain their thoughts

and the possible origin of their ideas.

4. Summarise some of the conversation

Henning et al. state that interviewers can verify that they have correctly understood

the interviewee by summarising parts of the conversation as it evolves. The

following interview extract illustrates this part of the interview:

Researcher: You wrote: “the driver of the truck will take less impact because of its size and

mass, and the truck will make the car move in the same direction.” Tell me more

about why you think the truck will take less impact because of its mass?

Student 2: I think it is because of the material which it is made of, it’s, a car it’s more like a, I

don’t want to say plastic, because there are some parts, like it’s made out of

plastic, more than the truck, you know, …

Researcher: Ok, you said that the truck will take less impact on its materials that it’s made of,

what is impact?

Student 2: Impact is the, (pause) for example, a car right, um, put it um,… ish, ok, …, impact

is the amount of force um, an object can take, but then, it gets destroyed in a kind

of way, like when it impacts, yah.

Researcher: So it’s the amount of force that it can take?

Student 2: Yah.

Researcher: O.K., so you are saying the, the truck can take more force than what the little car

can take.

5. Clarification of concepts

The interviewer may also ask the interviewee to explain the meaning of certain

concepts used by the interviewee. This practise is particularly helpful as it enables

the interviewer to find out what the interviewee comprehends about the concept.

The following are examples of such clarification, extracted from the student

interviews:

Researcher: You said that: “the cut-off switch is important because once there is an overflow

of power into one plug and it is damaging your devices it is not recommended if

83

such a similar thing happens to pull the plug connected because that can result in

your death.” What is power?

Student 2: The amount of work that can be done.

Researcher: You wrote: “wire P is a better conductor, because it is at a higher potential

difference than Wire Q.” Tell me more about why, uhh, the higher potential

difference would make it a better conductor. Why do you think it works like that?

Student 2: For some reason I think when something has the potential the high potential

difference it has the better conductor.

Researcher: O.K., what is potential difference?

Student 2: It’s the voltage of the umm … conductor or...

Researcher: O.K, and what is voltage?

Student 2: The measurement of umm …aah …umm …can’t really think what that is now um

(pause).

6. Keep an eye on the recording

Henning et al. reminds interviewers to check the recording device periodically during

interviews. Since I was using a tape recorder, which runs out of tape every 40

minutes, this was valuable advice.

7. Rounding off

After running through the pre-set questions and gaining clarification where

necessary, the time was almost up, so I checked if there was anything that the

participant would like to add or ask. Then I expressed my appreciation for the

participant’s participation and greeted the participant.

Each student and teacher interview followed this same process and lasted

approximately 30 minutes.

3.6.2.8 Recording the interview data

I transcribed the first interview word for word, typing and saving the data directly onto

my computer. During the transcribing process I already started to notice correlations

between the interview and exam-script data. Henning et al. (2004, p.127) states that:

“Qualitative analysis takes place throughout the data collection process. As such the

84

researcher will constantly reflect on impressions, relationships and connections while

connecting the data.” After transcribing the first set of data, I proceeded with the next

interviews. As I continued with the interviews I realised that there were similarities

between the students’ ideas and understanding, as well as similarities between the

interviewees’ responses and the exam-script responses. I recorded these connections

as I went along. I completed the interviews over a period of four days. Thereafter, I

transcribed the rest of the student and teacher interviews verbatim, including other

details such as pauses. The transcripts of both the student and teacher interviews are

included as appendix N – O.

3.6.2.9 Follow-up communication with the interview participants

Since research should be beneficial to the participants (Greene & Hogan, 2005), I gave

the teachers and students feedback on the findings of the study. I returned the students’

worksheets to them, with individual, detailed feedback. Copies of each student’s

worksheet were given to the teachers. I also included sufficient copies of a

memorandum with extended explanations and common misconceptions for the perusal

of both students and teachers. The extended memorandum is included as appendix K.

3.7 CONTRUCTING EVIDENCE – DATA ANALYSIS

In this study both a qualitative and a quantitative analysis of the exam-script data was

conducted. Thereafter, a computer-assisted qualitative analysis of both the exam-script

and interview data was conducted. These processes of analysis are discussed in this

section.

3.7.1 Qualitative analysis of the exam-script data

In this section I will discuss how I identified student misconceptions as revealed in the

exam-script data and why I focused the analysis on the student responses to

explanation-type questions. Next I will discuss how I designed an explanation-

classification grid and used it to classify the student misconceptions according to their

explanations.

85

3.7.1.1 Identifying the misconceptions

Since this study aims to identify common misconceptions, it was necessary to decide

exactly how misconceptions would be identified from student responses. According to

Clerk and Rutherford (2000, p.704), a misconception “fails to match the model accepted

by the mainstream science community in a given situation.” My working definition of a

misconception, as discussed in chapter 2, is: a misconception is a believable

conception which differs from the corresponding scientific conception. Although it

would be difficult to measure the degree to which students believe their alternative

conceptions, I would be able to identify student conceptions that differ from the

corresponding scientific conception. Hence, I decided that I would classify student

responses that are conceptually different to the answers supplied in the memorandum

as a misconception.

After an initial literature review, it became evident that I should not use the students’

responses to the multiple choice questions to identify possible misconceptions.

Although many research instruments employ a multiple-choice format to identify

misconceptions, Clerk and Rutherford (2000) raise questions concerning the validity of

using multiple-choice questions for diagnosing misconceptions. They argue that

students often misinterpret the question due to language barriers and then choose an

incorrect answer based on the misinterpretation. Also, Larrabee, Stein and Barman

(2006) point out that one of the main problems with this format is that it is difficult to

develop alternative responses that reflect the full range of students’ conceptions,

including misconceptions, about a particular idea. Students may also guess an incorrect

answer because they really do not know the subject content. Such incorrect answers

may then be misdiagnosed as a misconception.

Studies have revealed that calculation problem-solving questions have also been

problematic for uncovering misconceptions because students may be able to use

algorithms to solve these problems but may lack conceptual understanding (Cromley &

Mislevy, 2004; Goldring & Osborne, 1994; Hunt & Minstrell, 1994; Papaevripidou,

Hadjiagapiou & Constantinou, 2005). In view of these difficulties in identifying and

86

analysing student mirsconceptions, this study attempts to broaden our understanding of

student misconceptions by classifying misconceptions evident in student explanations.

Hence, I set about identifying the questions in the examination paper which would elicit

an explanation response from the students. Twelve of the questions from the

examination are explanation-type questions.

3.7.1.2 Designing the classification-grid

I designed the classification-grid as a research instrument with the purpose of

classifying misconceptions according to the explanation-type offered. I based my design

on the ten Dagher and Cossman explanation-types. Dagher and Cossman (1992)

generated ten types of explanations while exploring the nature of explanations in high

school classrooms. Moore and Harrison (2004) then employed their categorisation of

explanation-types in describing students explanations on the floating and sinking of

objects. These ten explanation-types can be described as follows:

Analogical: A story that parallels the unfamiliar phenomenon, e.g., “it can float because

it’s like a submarine.”

Anthropomorphic: Attributing human characteristics to a phenomenon, e.g., “she floats

because she is lighter.”

Functional: Explained as a consequence of function (natural), e.g., “It floats because of

the air in it.”

Genetic: Uses a sequence of events (what, not why) and resembles description by

stating “what happens, not why it happens”, e.g., “it floated on top of the water.”

Mechanical: A relationship because of physical (shape/design) properties (pressure),

e.g., “it floats because of its shape.”

Metaphysical: Where a supernatural agent is identified as a cause of the phenomena,

e.g., “God made it float.”

Practical (how to): Instructions of how to perform physical or mental operations, e.g., “to

float you need to do …” this is regarded as description rather than explanation.

87

Rational: A clearly identifiable scientific statement or story where scientific evidence is

given for a claim, e.g., “a boat floats because the up-thrust from the water equals the

weight.”

Tautological: This is a circular story, e.g., “it floats because it is made to float.”

Teleological: It has to or needs to happen as part of the phenomena, e.g., “boats float

because we need them to float.”

I designed the misconception classification-grid as a table, with spaces to fill in data with

regard to a single student’s exam responses. The grid includes columns representing

the ten Dagher and Cossman explanation-types and rows representing the 12

explanation-type questions asked in the examination. The grid enables one to classify

the student responses as a particular type of explanation. This was critical in my

analysis as I was then able to understand the characteristics of the explanation, which

led me to effectively diagnose a misconception that was inherent to a type of

explanation. Besides the columns for the ten explanation-types, I included columns to fill

in when the student held no misconception or when the classification of the

misconception was inconclusive. Responses that were constructed so poorly that their

meaning was unclear were to be classified as inconclusive. I also included spaces to

record the marks obtained by the student for each explanation-type question, the total

achieved by the student for the explanation-type questions and the total achieved by the

student for the Physics examination. I did this so as to be able to compare the students’

performance in explanation-type questions and non-explanation-type questions. I added

space to record the student’s responses, which I used when the responses represented

a richly descriptive expression of a misconception. On completion of the classification-

grid I submitted the grid to my supervisor, who examined and refined it.

3.7.1.3 Preliminary classification

With the grid refined, I performed a preliminary classification of 100 scripts together with

two other coders. The coders are both suitably qualified, experienced science teachers.

According to Franzosi (n.d., p.187), it is “good practice to test the reliability of each

coding category by having different coders code the same material.” When a

88

misconception became evident in an explanation, it was labelled according to the type

of explanation offered. For example, a misconception in a mechanical explanation was

referred to as a mechanical misconception. This approach therefore provided a way by

which misconceptions in scientific explanations could be categorized. The student

responses in the exam scripts were then classified into the following categories:

• No misconception, where the student explanation was conceptually correct.

• Misconception, where the students explanation is inconsistent with the commonly

accepted scientific explanation.

• Inconclusive, where the response was marked incorrect, but it could not be

established that a misconception existed.

• No response, where the student did not attempt the question.

The category of “inconclusive” was not a part of the original classification, but I was

forced to include it after it became clear to me that many responses that were incorrect

lacked sufficient evidence to be coded as a misconception. I do not contend here that

students who produced these responses did not have a misconception inherent to their

explanation, but merely that there was a lack of evidence in the explanation for us to

infer that a misconception existed. Many cases that fell into this category suggested that

the students had either not read the question properly or that they did not understand

the question due to poor language skills or lack of knowledge on the specific subject

content. Student responses that were catergorised as “inconclusive” in terms of

misconceptions did not focus on what was demanded in the question. For example, in

answering question 5.3 students were expected to use Physics principles to explain

how the masses of the cars affect the risk of injury during a collision. The following

examples show how students neglected to consider the masses of the cars and instead

focused on another aspect in the question.

It is too dangerous for people who are inside the car because they will all have an accident that is

caused by the high speed of the cars.

89

Modern cars are designed to crumple partially on impact, and it decreases the dangers of risk in

the injury.

In the first example, the student refers to the speed of the cars, which despite being a

factor in the risk of injury, was not the focus of this question. In the second example, the

student refers to modern cars which crumple upon impact. Although this is correct, it

again represents a case where the student had missed the focus of the question.

As part of the preliminary classification we also recorded specific student responses that

expressed detailed misconceptions, commented on significant issues such as poor

language usage and misunderstanding of the question and recorded the marks

achieved by the students for each explanation-type question and for the Physics paper

as a whole. The preliminary classification helped to verify the reliability of the

classification process. Intercoder reliability was 86%. Where disagreement did exist it

was resolved through discussion.

During the preliminary classification we found five specific misconceptions that were

occurring frequently. Together with my supervisor, I decided to add them onto the

analysis grid in order to determine the exact frequency at which these misconceptions

were occurring in the sample provided. The final classification-grid is included as table

3.1, next:

90

Table 3.1: Final misconception classification-grid


Common

misconceptions

He

av

ier

car

-mo

re

imp

act

En

erg

y is

lost

R l

ess

wh

en

pa

ralle

l R

bu

rns

Sp

lit-r

ing

Vo

lta

ge

incr

ea

ses

Scr

ipt

nu

mb

er:

Stu

de

nt'

s to

tal

for

the

ex

pla

na

tio

n Q

's:

/32

Stu

de

nt'

s a

nsw

er

Stu

de

nt'

s m

ark

for

the

Ph

ysi

cs

pa

pe

r: /1

50

No misconception

Inconclusive misconception

Teleological :

Part of phenomenon

Tautological :

Back to question

Rational expl: Evidence

Practical expl: How to

Metaphysical: Supernatural

Mechanical:

Physical properties

Genetic : What not why

Functional explanation

Anthropomorphic :

Human attributes

Analogical explanation:

Familiar situation

Question totals 2

3

1

2

2

2

2

4

4

2

4

4

32

Students’ marks

Qu

est

ion

s

5.2

Wh

y m

ay

co

nse

rva

tio

n o

f p

no

t

be

va

lid?

5.3

Wh

y a

re p

ass

en

ge

rs in

a h

ea

vie

r

car

less

lik

ely

to

ge

t in

jure

d?

7.5

Wh

at

ha

pp

en

s to

Ek

th

at

is n

ot

con

ve

rte

d t

o e

lect

rica

l en

erg

y?

9.3

De

scri

be

dif

fra

ctio

n p

att

ern

9.4

Na

me

1 s

imila

rity

an

d 1

dif

fere

nce

ob

serv

ed

be

twe

en

sin

gle

an

d d

ou

ble

slit

pa

tte

rn

9.5

Will

pa

tte

rn b

e s

ee

n w

ith

a li

gh

t

bu

lb?

Re

aso

n?

10

.2

Is

B –

or

+?

Re

aso

n?

11

.2 P

or

Q b

ett

er

con

du

cto

r?

Exp

lain

.

12

.3 H

ow

wil

l V c

ha

ng

e if

R b

urn

s

ou

t/ R

ea

son

.

13

.1 T

yp

e o

f g

en

era

tor?

Re

aso

n.

14

.3 E

xpla

in w

hy

cu

t o

ff s

wit

ch is

imp

ort

an

t.

15

.3 I

nte

nsi

ty in

cre

ase

d.

Exp

lain

wh

at

ha

pp

en

s to

en

erg

y a

nd

no

. o

f

ph

oto

-e

To

tals

:

Co

mm

en

ts:

91

3.7.1.4 Further classification of student responses in the sample of exam

scripts

After the preliminary classification process and final refinements to the classification-

grid, I continued to fill in a classification-grid for each one of the 921 exam scripts. I

followed the same process of classification and recording as in the preliminary

classification, classifying each student response as a particular type of explanation. I

also continued to record specific student responses that represented misconceptions,

commented on significant issues as they became apparent and recorded the marks

achieved by each student. In addition, I recorded whether or not each student held any

of the five common misconceptions that I had added onto the classification-grid after the

preliminary classification process. The process of classification extended from July 2009

to December 2009. Examples of completed classification-grids are included as

appendix L.

3.7.2 Quantitative analysis of the exam-script data

The exams contained numeric data, such as marks allocated to specific questions and

marks achieved by individual students. Burton et al., (2008, p.146) explain the following:

Research reports that make effective use of both quantitative and qualitative data will often lead

with the quantitative evidence to provide an immediate point of impact as a ‘headline’ and then

follow it up and enrich the interpretation and analysis through the introduction of the qualitative

sources.

The purpose of the quantitative analysis was to indicate the frequency of

misconceptions, the frequency of various explanation-types and the performance of

students in explanation-type questions, thereby highlighting the need to delve further

into the nature of these misconceptions and explanation-types.

In order to calculate the frequency of misconceptions, I made use of the data on the

classification-grids which had been filled in for each student during the data-collection

phase of this study. I used the data to calculate the following proportions: percentage of

misconceptions revealed in explanations, percentage of responses with no

92

misconception, percentage of misconceptions revealed for each explanation-type,

percentage of no responses and percentage of responses classified as inconclusive

with regard to misconceptions.

In order to determine the performance of students in explanation-type questions I

calculated the average percentage achieved for explanation-type questions and the

average achieved for non-explanation-type questions. I also calculated the percentage

of explanation-type questions and non-explanation-type questions present in the

examination paper. I did this in order to explore the possible emphasis on exemplar-

type calculations and rote-learning as the majority of non-explanation-type questions fall

into these categories.

3.7.3 Computer-Assisted Qualitative Data Analysis

Both the exam scripts and interview transcriptions contain information-rich text. I typed

out several information-rich student responses which I extracted from the exam scripts. I

copied these responses and the interview transcriptions onto documents called primary

documents, using the computer software Atlas.ti. I used the software to systematise the

data, while understanding that it remains the researcher’s task to code the data and

organise the analysis (Smit & Lautenbach, 2009).

When working with qualitative data there are many possible ways to process data into

“patterns of meaning”, however it is crucial to fit the method of analysis to the research

design (Henning et al., 2004, p.102). Hence I decided to select qualitative content

analysis which involves seeking emerging patterns. In order to find patterns I read

through all of the interview transcripts, thereby attaining a comprehensive idea of the

data. As I read through the data a second time, I started to identify and highlight

meaningful words or phrases that captured common misconceptions and their

relationship with explanation-types. I extracted these meaningful words and phrases

from the data and reduced them to codes which convey the essence of the data. I

constructed 50 codes and organised them with the assistance of Atlas.ti, as indicated in

table 3.2:

93

Table 3.2: Analysis codes

HU: Student Misconceptions in grade 12 Physics.hpr1 File: [D:\Celeste (F)\Celeste\STUDIES\Masters\atlasti\Student Misconceptions in grade 12 Physics.hpr1.hpr6] Edited by: Super Date/Time: 10/07/02 08:14:20 AM

Application of theory is problematic Assessment as a barrier to diagnosing and remedying misconceptions Calculation questions are more straightforward Confused: Between internal and external R Confused: conservation of Ek vs p Confused: Generators vs motors Confused: difference btw laser and light bulb, coherent Confused: mass and weight, using interchangeably Confused: series and parallel Construction of a functional misconception Construction of a functional misconception regarding resistance Construction of a genetic misconception Construction of a genetic misconception: Why current increases when adding appliances in multi-plug Construction of a genetic Misconception: voltage across parallel resistors Construction of a mechanical misconception Construction of a metaphysical misconception Construction of a practical misconception Construction of a rational misconception Construction of a tautological misconception Construction of a teleological misconception Construction of an analogical misconception Construction of an anthropomorphic misconception Electricity misconceptions Experiments are important Frequent misconception: A heavier car exerts a greater force on a lighter car during a collision Frequent misconception: Cut-off switch increases V, safe and saves

Frequent misconception: Energy is lost Frequent misconception: R decreases when a parallel resistor is removed Frequent misconception: Split rings Hidden construct: Teleological, inconclusive and no response Incomplete constructions: Mechanical, Genetic, Functional, Tautological, Metaphysical and Practical Inconclusive misconception Language as a source of misconceptions Language problem Students answer questions without true understanding Students don't understand what is expected in explain questions Students forget electricity done in grade 11 and examined in grade 12 Mathematical literacy Misconception: Conductivity depends on both I and V, not only I Misconception: matter is created Misconception: momentum Misconceptions influences and is influenced by class atmosphere Newton's third law doesn't make application sense to the student No training or meetings on misconceptions Remedies for misconceptions_1 Simple construct: Anthropomorphic and analogical Sources of misconceptions Struggles with the concept of potential difference Teach principles without revising basic principles Write it exactly like in the book


Next, I allocated codes to the data that matched the themes in the data, thereby

breaking-down and conceptualising the data into themes (Strauss & Corbin, 1990), this

process is known as open coding (Henning et al., 2004). The following are examples of

the open coding performed in this study: The code “Energy is lost” was attached to the

data “some of the energy is lost through sound”, the code “Mechanical explanation” was

attached to the data “Because it’s mass is greater.”

94

I also used “In-Vivo” coding (Atlas.ti), where the selected text itself becomes the code.

For example, I selected the data: “Like I want to say something and I try to write it

exactly like in the book, and if I forget I get blank and then just move onto the next

question, and think I will come back to it” and coded it as “Write it exactly like in the

book.”

The next step was to reconstruct the data, by clustering interrelated codes together. For

example: the codes “Application of theory is problematic”, “Calculation questions are

more straightforward”, “Language problem”, “Students answer questions without true

understanding”, “Students don't understand what is expected in explain questions”,

“Students forget electricity done in grade 11 and examined in grade 12” and “Write it

exactly like in the book”, were clustered together to form the family: “Assessment as a

barrier to diagnosing and remedying misconceptions.” These codes which had been

attached to both exam-script data and interview-data are all related to the relationship

between assessment and misconceptions which also emerged in the literature review.

Another example is the clustering of the codes: “Construction of a tautological

misconception”, “Frequent misconception: Energy is lost”, “Inconclusive misconception”

and “Misconception: matter is created” to form the family: “Hidden constructions:

Tautological, inconclusive and no response”. These codes all relate to the hidden nature

of misconceptions, which makes their diagnoses complex and calls for more emphasis

on assessment and teaching strategies that promote conceptual understanding and

reconstruction of misconceptions.

I repeated the clustering process until I had narrowed down the clusters, also known as

families, to seven main themes or findings. These families, which supply valuable

information regarding common misconceptions and their relation to explanations, have

been extracted using the computer software, and are listed in table 3.3:

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Table 3.3: Code families HU: Student Misconceptions in grade 12 Physics.hpr1 File: [D:\Celeste (F)\Celeste\STUDIES\Masters\atlasti\ Student Misconceptions in grade 12 Physics.hpr1.hpr6]

Edited by:Super Date/Time:11/09/17 12:49:43 PM ______________________________________________________________________ Code Family: Assessment as a barrier to diagnosing and remedying misconceptions Created: 10/07/01 10:44:49 AM (Super) Codes (7): [Application of theory is problematic] [Calculation questions are more straightforward] [Language problem] [ Students answer questions without true understanding] [ Students don't understand what is expected in explain questions] [ Students forget electricity done in grade 11 and examined in grade 12] [Write it exactly like in the book] Quotation(s): 39 ______________________________________________________________________ Code Family: Hidden constructions: Tautological, inconclusive and no response Created: 10/07/01 10:43:06 AM (Super) Codes (4): [Construction of a tautological misconception] [Frequent misconception: Energy is lost] [Inconclusive misconception] [Misconception: matter is created] Quotation(s): 14 ______________________________________________________________________ Code Family: Incomplete constructions:Mechanical, Genetic, Functional, Teleological and Practical Created: 10/06/30 05:24:35 PM (Super) Codes (20): [Confused: Between internal and external R] [Confused: conservation of Ek vs p] [Confused: Generators vs motors] [Confused: series and parallel] [Construction of a functional misconception] [Construction of a functional misconception regarding resistance] [Construction of a genetic misconception] [Construction of a genetic misconception: Why current increases when adding appliances in multi-plug] [Construction of a genetic Misconception: voltage across parallel resistors] [Construction of a mechanical misconception] [Construction of a practical misconception] [Construction of a teleological misconception] [Frequent misconception: A heavier car exerts a greater force on a lighter car during a collision] [Frequent misconception: Cut-off switch increases V, safe and saves] [Frequent misconception: R decreases when a parallel resistor is removed] [Frequent misconception: Split rings] [Incomplete constructions: Mechanical, Genetic, Functional, Tautological, Metaphysical and Practical] [Misconception: Conductivity depends on both I and V, not only I] [Misconception: momentum] [Struggles with the concept of potential difference] Quotation(s): 46 ______________________________________________________________________

96

The computer software enabled me to code the data and cluster the 50 codes more

efficiently as it is able to pull together data with common codes.

Code Family: More complex constructions: Rational misconceptions Created: 10/07/01 11:33:32 AM (Super) Codes (3): [Construction of a rational misconception] [Frequent misconception: A heavier car exerts a greater force on a lighter car during a collision] [Frequent misconception: R decreases when a parallel resistor is removed] Quotation(s): 20 ______________________________________________________________________ Code Family: Relationship between language and misconceptions Created: 10/07/01 10:50:18 AM (Super) Codes (9): [Application of theory is problematic] [Confused: difference btw laser and light bulb, coherent] [Confused: mass and weight, using interchangeably] [Frequent misconception: Energy is lost] [Language problem] [Misconception: matter is created] [Newton's third law doesn't make application sense to the student] [Struggles with the concept of potential difference] [Write it exactly like in the book] Quotation(s): 52 ______________________________________________________________________ Code Family: Remedies for misconceptions Created: 10/07/01 10:54:55 AM (Super) Codes (7): [Experiments are important] [Language problem] [ Students don't understand what is expected in explain questions] [Mathematical literacy] [No training or meetings on misconceptions] [Sources of misconceptions] [Teach principles without revising basic principles] Quotation(s): 34 ______________________________________________________________________ Code Family: Simple constructions: Anthropomorphic, analogical and metaphysical Created: 10/07/01 11:42:43 AM (Super) Codes (3): [Construction of a metaphysical misconception] [Construction of an analogical misconception] [Construction of an anthropomorphic misconception] Quotation(s): 1


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3.8 CLEANING UP THE CONSTRUCTION SITE – DATA STORAGE

The data have been stored in such a manner as to ensure the confidentiality of

participants. It will be kept under lock and key for 2 years after the study, after which it

will be destroyed.

3.9 CONCLUSION

In this chapter I have discussed the processes of designing my qualitative content

analysis based on the foundations of social constructivism and the logics of

contextualisation, discovery and diachronicity. I then discussed the collection of data by

means of identifying the misconceptions in both the exam scripts and discursively

oriented interviews. Lastly, I discussed the data analysing methodologies of coding and

clustering as assisted by computer software. Now it is time to move to the next chapter

where I will discuss the results that I have found emerging from the data.

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CHAPTER 4

PRESENTATION, DISCUSSION AND INTERPRETATION OF THE RESEARCH

RESULTS

4.1 INTRODUCTION

This chapter commences with a presentation of data regarding the performance of

students in explanation-type questions as opposed to non-explanation-type questions.

Next, the distribution of explanation and non-explanation type questions, in the 2008

NSC Physics examination, is presented. The chapter continues with a presentation of

the frequency of the misconception-types that were generated in this study. These

misconception-types were generated according to the Dagher and Cossman (1992)

explanation-types. These misconception-types are also discussed and illustrated using

examples from the exam-script and interview data. In addition, the frequency of five

common misconceptions is presented and these five common misconceptions together

with other misconceptions identified through this study are discussed. The chapter ends

with an interpretation of what the misconception-types reveal in terms of possible

sources of misconceptions.

4.2 STUDENT PERFORMANCE IN EXPLANATION-TYPE QUESTIONS

The aims of this study are to identify student misconceptions as revealed in student

explanations and to classify these misconceptions according to the types of

explanations in which they are revealed. I also aimed to determine how students

perform in explanation-type questions. According to Bryce and MacMillan (2009)

students perform poorly in explanation-type questions. In this section I present data on

the performance of students in explanation-type questions. I have also included data on

the performance of students in non-explanation-type questions, as the comparison

between the performance of students in explanation and in non-explanation-type

questions highlights the poor performance of students in explanation-type questions.

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On analysing the exam scripts I found that the sample of 921 students achieved an

average of 17, 4% for the explanation-type questions, and an average of 25, 8% for the

non-explanation-type questions, and an overall average of 24% for the Physics exam in

its entirety. A graphical presentation of these results follows in figure 4.1:

Figure 4.1: A bar graph of the performance of a sample of students


As can be seen by the above results, the poor performance of students in explanation-

type questions decreases the overall performance of the sample by 1,8%. Students

performed 8,4% worse in explanation-type questions than in non-explanation-type

questions.

The poor performance of students in explanation-type questions may be attributed in

part to the fact that explanation-type questions expose students’ understanding and

misconceptions (Graesser et al., 1996; Sevian & Gonsalves, 2008). On the other hand,

students’ responses to the type of non-explanation-type question that can be mastered

by rote learning do not effectively reveal their true level of understanding (Mintzes et al.,

2001). According to Harrison et al., (1999), students are able to treat exemplar-type

calculation questions as simple algorithms. These exemplar-type calculation questions

are found as examples and in exercises within textbooks. Students study these

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examples and practice them for homework. This allows students to complete these

types of calculations successfully in assessments without revealing their

misconceptions and without changing their incorrect conceptions. The following

comment was made by one of the student interviewees regarding exemplar-type

calculation questions: “That’s because it’s straight forward, you know the formula and

you just do it.”

Students may also perform poorly in explanation-type questions because they are not

aware of what is expected from them in the answering of these types of questions. This

problem may arise due to the overemphasis on non-explanation-type questions and is

discussed in the next section.

4.3 DISTRIBUTION OF EXPLANATION AND NON-EXPLANATION QUESTIONS

In this section I present the distribution of explanation-type questions as opposed to

non-explanation-type questions in the 2008 NSC Physics examination paper. Of the 150

marks allocated to the Physics exam, 32 marks (21%) were allocated to explanation-

type questions and a substantially larger share of 118 marks (79%) was allocated to the

non-explanation-type questions. The non-explanation-type questions consisted largely

of selected response questions and exemplar-type calculations. The selected response

questions consisted of multiple-choice and true or false questions. The distribution of

question-types is illustrated in figure 4.2:

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Figure 4.2: A pie chart of the question-types in the NSC 2008 Physics exam


The data illustrate the emphasis that examiners place on non-explanation-type

questions. This emphasis focuses the attention of teachers and students on non-

explanation-type questions. Most non-explanation-type questions can be mastered by

rote learning. Even the calculation-type questions found in school exams rarely differ

from the examples found in textbooks and in previous exams. This focus leads to very

little time being spent on the development of students’ conceptual understanding. It is

important that examiners do not merely change the emphasis from non-explanation-

type to explanation-type questions without aiming to promote conceptual learning, as

this may lead to more rote learning.

4.4 DESCRIBING THE DIFFERENT TYPES OF MISCONCEPTIONS AND THEIR

FREQUENCY

Each of the 11052 student exam-script responses [twelve responses for each student in

the sample of 921 students] was coded into one of the following categories:

• Misconception, where the student’s explanation is inconsistent with the

commonly accepted scientific explanation.

• No misconception, where the student explanation was conceptually correct.

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• Inconclusive, where the response was marked incorrect, but it could not be

established that a misconception existed.

• No response, where the student did not attempt the question

As mentioned in chapter 3 the category of “inconclusive” was not a part of the original

classification, but because many responses lacked sufficient evidence for them to be

coded as misconceptions I was forced to include the category of “inconclusive”.

Each exam-script response revealing a misconception was then classified according to

the Dagher and Cossman (1992) explanation-types. Classifying each response as a

specific type of explanation enabled me to diagnose the misconception that was

inherent to a type of explanation. For example, where a student advanced a mechanical

explanation I was able to focus on his/her conception of the relationship between a

physical property of an object and its behaviour and then explore this relationship for a

misconception. Such responses were then classified as a mechanical misconception.

The data regarding the occurrence of various types of misconceptions are tabulated in

table 4.1 and illustrated in figure 4.3:

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The most prevalent misconceptions were located in genetic and mechanical

explanations. Both table 4.1 and figure 4.3 indicate that these two types of explanations

together yielded 77,7% of the identified misconceptions. In the genetic explanations

students explained what happened instead of why it happened. In the mechanical

explanations students explained the phenomenon by supplying the physical properties

of an object as the only evidence.

In total, 11,6% of the identified misconceptions were classified as functional

explanations. The majority of these misconceptions occurred in question 14.3 where

students were asked to explain the importance of the cut-off switch in a multi-plug.

Students have various misconceptions regarding the function of the cut-off switch.

These include the misconceptions that it lowers the voltage when the voltage gets too

much, that it saves electricity by switching off when electricity usage is too high, that it

Types of Responses Number of responses

Percentage of responses (%)

Percentage of misconceptions (%)

Misconception

Analogical 0 0 0 Anthropomorphic 4 0.04 0.1 Functional 352 3.2 11.6 Genetic 1238 11.2 40.9 Mechanical 1116 10.1 36.8 Metaphysical 0 0 0 Practical 7 0.06 0.2 Rational 151 1.3 5 Tautological 117 1.1 3.9 Teleological 46 0.4 1.5 Sub-total 3031 27.4 100

No misconception 1285 11.6

Inconclusive 5787 52.4

No response 949 8.6

Total 11052 100

Table 4.1: Types of responses identified in a sample of student exam scripts


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can prevent a person from getting shocked, that it works like a normal switch which can

be switched off, and that it can split the voltage between various appliances. These

misconceptions may have occured because the function of a cut-off switch is not

directly addressed in the syllabus.

Figure 4.3: A bar graph of the frequency of misconception-types in a sample of

student exam scripts


Figure 4.3 illustrates that a total of 5% of the identified misconceptions were classified

as rational explanations. Students constructing these explanations attempted to apply

laws of Physics to explain phenomena, but did so incorrectly. When attempting a

rational explanation students often only consider two variables in an equation as if the

third variable automatically remains constant, which it often doesn't. For example,

students answer that the heavier car has more momentum because p=mv, thereby

neglecting the velocity variable.

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A total of 3,9% of the identified misconceptions were classified as tautological

explanations. In these explanations students answered the question by circling back to

the question. An example of such an explanation occurred in response to question 5.3.

In this question, students were asked to use principles of Physics to explain why a traffic

officer would be correct in stating that the risk of injury for passengers in a heavier car

would be less than in a lighter car. In response, a student wrote: “It is because he

mentions that for cars involved in a head-on collision, the risk of injury for passengers in

a heavier car would be less than for passengers in a lighter car."

In total, 1,5% of the identified misconceptions were classified as teleological

explanations. In these explanations students incorrectly explained an occurrence as

being part of a phenomenon. For example, in question 5.2 students were asked why the

conservation of momentum may not be valid in a specific collision. Students then

answered with the misconception that momentum was not conserved because the

collision was inelastic or elastic. Olivier (n.d., a, p.70) explains that “Inelastic collisions

are collisions where kinetic energy is not conserved.”

Very few misconceptions were classified as either practical or anthropomorphic

explanations, only 0,3% collectively. In practical explanations, students explain how

things should be done instead of explaining why things happen or are important. An

example of a misconception that was exposed in a practical explanation is that cut-off

switches should be put off. Cut-off switches are trip-switches and cannot be put off to

save electricity. This misconception is illustrated in the following student responses: “It

is important to cut off appliances that are not in use. It's more expensive because you

are paying for electricity supplied to appliances not in use" and "The cut of switch is

important because when the multi-plug is over loaded, switch on the cut-off switch

quick." It is clear from these responses that students are incorrectly explaining what

should be done with cut-off switches instead of explaining why they are important. The

few students who constructed anthropomorphic explanations seemed to attribute

human attributes to things as a manner of speech rather than actually believing that an

object has those human attributes. Students and teachers do this in an attempt to relate

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better with the abstract nature of scientific phenomena (Dagher & Cossman, 1992).

Treagust and Harrison (2000, p.1165) argue that anthropomorphisms are “acceptable

elements of effective pedagogical content explanations because teachers’ pedagogical

content knowledge is neither pure science nor is it intended to be.” Anthropomorphisms

are often used in order to bridge the gap between scientific and everyday language,

because students often do not know the correct scientific terms. The following student

responses illustrate the construction of anthropomorphic explanations: "So that

electrons would get time to rest, when switch it on they perform a good work" and "If the

resistor burns out the voltmeter will decrease because the voltmeter is helping out the

resistor.” In these explanations the one student attributed the human action of resting to

inanimate electrons instead of explaining that the electric current stops flowing and

another student described a voltmeter as being able to help out a resistor.

No misconceptions were identified in analogical and metaphysical explanations. This is

likely due to the fact that teachers only use analogies in certain sections of work where

they are acquainted with analogies that correspond to the content, and the content that

was assessed in the exam that was analysed did not lend itself readily to the use of

analogies. Nevertheless, it is important for teachers to be careful when using analogies.

Teachers must make sure that students are aware of not only the similarities between

the analogy and the target, but also the differences between them. Thiele and Treagust

(1991, p.6) warn that “Teachers should not assume that students are capable of

effecting correct analogical transfer but, rather, should provide explicit instruction on

how to use analogies and provide opportunity for considerable classroom discussion on

the subject.” Treagust and Harrison (2000, p.1163) also advise that “students need

guidance in mapping the shared and unshared attributes if understanding is to be

maximized.” Students also did not refer to any supernatural causes in their

explanations. Dagher and Cossman (1992, p.369) classify metaphysical explanations

as “spurious”. Spurious or “counterfeit” explanations (Gilbert et al., 1998b, p.191) are

formulated in such a manner that they cannot be proven as true or false, as opposed to

genuine or authentic explanations which are falsifiable (Trusted as quoted by Dagher &

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Cossman, 1992). Gilbert et al. (1998b, p.191) warn that spurious explanations may be

seen as “legitimate in certain cultural contexts.”

4.5 FIVE COMMON MISCONCEPTIONS

In the sample of 921 scripts, five specific misconceptions occurred frequently. I decided

to focus my subsequent analysis on these misconceptions.

4.5.1 The frequency of five common misconceptions

The frequency of these five misconceptions is indicated in figure 4.4:

Figure 4.4: A bar graph of the frequency of common misconceptions as

revealed in a sample of student exam scripts


The graph shows that almost a quarter of the student sample held the most frequent

misconception revealed in this study, the misconception that a heavier car exerts more

impact during a collision.

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4.5.2 The nature of five common misconceptions

In this section the nature of the five common misconceptions is discussed. During the

discussion I will draw upon data collected from both the exam-script responses and

student interviews. I will also refer to the explanation-type in which the misconception

was revealed because it reveals information regarding the nature of the misconception.

In order to determine the explanation-types in which the common misconceptions are

revealed, I studied the misconception classification-grids, which were completed for

each exam script in the sample. I counted the number of responses classified according

to each explanation-type for each separate question in the 2008 NSC Physics

examination. These results are shown in table 4.2:

Table 4.2: Types of student responses classified per question


Qu

es

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um

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No

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ep

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n

Inco

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lusiv

e

No

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on

se

Mis

co

nc

ep

tio

ns

Types of explanations revealing misconceptions

Mech

an

ica

l

Ge

ne

tic

Fu

nctio

nal

Ra

tio

nal

Ta

uto

logic

al

Tele

olo

gic

al

Pra

ctica

l

An

thro

pom

orp

hic

An

alo

gic

al

Meta

ph

ysic

al

5.2 48 195 30 648 267 332 4 5 15 24 2 0 0 0

5.3 43 177 31 670 396 175 0 71 16 12 0 0 0 0

7.5 74 610 99 138 1 126 1 5 4 1 0 0 0 0

9.3 123 710 75 13 2 1 1 1 6 2 0 0 0 0

9.4 109 695 80 37 27 3 0 0 6 1 0 0 0 0

9.5 125 663 77 56 24 25 1 2 2 1 1 0 0 0

10.2 263 537 24 97 7 78 5 1 4 1 1 0 0 0

11.2 190 463 14 255 181 50 2 8 13 0 0 0 0 0

12.3 13 435 75 394 149 154 9 47 31 2 0 2 0 0

13.1 191 610 45 79 4 69 2 2 0 1 1 0 0 0

14.3 19 312 119 473 19 114 324 8 3 1 2 2 0 0

15.3 87 381 280 171 39 111 3 1 17 0 0 0 0 0

Total 1285 5787 949 3031 1116 1238 352 151 117 46 7 4 0 0

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4.5.2.1 First common misconception: heavier cars exert more impact on lighter

cars during a collision

The first common misconception identified in this study appeared in student responses

to question 5.3 of the Physics exam. In question 5.3 students were asked to use

principles of Physics to explain why the risk of injury for passengers in a heavier car

would be less than for passengers in a lighter car. Question 5.3 is shown in figure 4.5:

Figure 4.5: An examination question on the collision between two cars

Source: DOE – November 2008 NSC grade 12 Physical Sciences (P1)

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A total of 670 misconceptions were identified for this question from the sample of 921

student responses. The majority (59%) of these misconceptions were in student

explanations that were coded as mechanical. In these explanations, students had a

misconception about how a physical property of an object explained its behaviour or a

phenomenon related to it.

A common misconception revealed in the students’ mechanical explanations was that

during the interaction between two objects the heavier object exerts a greater force on

the lighter object. This misconception was held by 219 students in the sample, and

represents 33% of the 670 misconceptions exposed by this question. Students who

constructed a mechanical explanation containing this misconception, focussed on the

physical property of mass to explain the interaction between two objects. The following

exam script response illustrates this misconception and the student’s focus on the

physical properties of the objects: “A lighter car will easily get crushed due to the mass

of the heavier. The heavier the mass, the greater the force.” This misconception was not

only evident in the exam-script responses but also in the pre-interview test and in the

interview data, as illustrated by the following responses by student interviewee one and

four respectively:

The heavier car will exert a much higher force than the lighter car.

The weight of the car influences like the force that the car exerts, so if a car is moving at a certain

speed, and then the lighter one is also moving at a certain speed too, then the heavier car tries to

brake, it’s going to take longer for it to brake, because of all of the weight on it than the smaller

one, so then the heavier one is going to exert more force than the smaller one, That’s why the

smaller one has more risk of getting injured than the heavier one.

The students’ focus on the mass of the cars was not the problem. The question required

students to consider the mass and then to discuss the relationship between mass and

acceleration. However, students exposed their misconceptions about mass by

constructing a mechanical explanation which focuses only on mass. The quotations

above also illustrate the misconception that mass, weight and force are similar

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properties of matter. This misconception causes students to use the terms

interchangeably as if they have the same meaning.

The misconception about heavier objects exerting more force contradicts Newton’s third

law and prevents students from properly understanding it. Students may even construct

explanations with both Newton’s third law and the misconception about heavier objects

alongside one another, as illustrated by the following exam-script responses:

Using Newton's third law the car with a heavier mass will exert a greater force on the car with a

lighter mass.

This is Newton’s third law – when object A exerts force on object B, object B will exert equal but

opposite force of object B. This is applied here because when a lighter car collides with a heavier

car, they will be greater opposite force exerted on a lighter car, but will result in injuries to the

passengers in a lighter car, during head-on collision.

During an interview a student expressed his experience of Newton’s third law as

follows:

Student 3: I heard an example once where they said that when a mosquito collides into a

car, the mosquito experiences the same force as the car experiences from the

mosquito.

Researcher: Do you believe that?

Student 3: I don’t know what they mean, that the force will be the same, because like, like to

me it doesn’t make much sense.

Yet another student interviewee, student six, explained that Newton’s third law cannot

be applied to a head-on collision: “But it can’t be because it isn’t closed.” This student

incorrectly applied the conditions for conservation of momentum to Newton’s third law,

which has no conditions.

Students did not only focus on the masses of the cars, in their mechanical explanations,

but also on the strength of the car materials. The following two exam-script responses

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show how students focused on the strength of the materials from which the cars are

made:

The passengers in a lighter car are more likely to get injured because it is made of weaker

material.

The passenger in a heavier car has weight and the material of the car has a higher mass and its

velocity is also high which means the car is very strong, as for the lighter car it is not strong.

Instead of focussing on the strength of materials, students ought to have explained the

relationship between the mass of the car and the change in velocity of the car by

referring to Newton’s Second Law of motion. However, by constructing a mechanical

explanation based on the strength of materials, students exposed the misconception

that stronger materials exert more force. The following interview data also illustrates this

misconception:

Researcher: You wrote: “the driver of the truck will take less impact because of its size and

mass, and the truck will make the car move in the same direction. Tell me more

about why you think the truck will take less impact because of its mass?

Student 2: I think it is because of the material which it is made of, it’s it’s, a car it’s more like

a, I don’t want to say plastic, because there are some parts, like it’s made out of

plastic, more than the truck, you know, it’s not plastic, plastic, but you know

that…, I don’t know that material it’s made off; and the truck has more weight,

you know there’s more stuff put on it and because of the material as well, so

when it collides it will move um the car… the same direction as the truck was

moving.

Although weaker materials may experience more bending and damage as a result of

force, they do not exert less force than stronger materials. Also, the fact that a weaker

material bends and breaks more, means that the contact time of the collision increases,

thereby decreasing the force of impact on both of the cars.

Students also constructed genetic explanations containing misconceptions. Genetic

explanations accounted for 26% of misconceptions for this question. In the genetic

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explanations that were offered, students focused on describing what happens instead of

providing scientific evidence regarding why the event happens. By focussing on what

happened, students exposed their misconceptions regarding the interaction between

two objects. This was evident in the following exam-script responses:

The heavier car overpowers the lighter car in the collision. The lighter car will be squashed but

the heavier car will be less squashed than the lighter car.

The heavy car is much more powerful and pushes the lighter car with a bigger force. It causes

more damage to it and injures the passengers.

In both responses students appear to have a naïve understanding of the relationship

between the mass of the car, its horsepower and the force it exerts upon impact. Firstly,

the above responses suggest that the car with larger mass is more powerful. This is

incorrect as the power of a body is defined as the rate at which that body does work

(Heyns et al., 1999). Although power is influenced by mass, because the work done on

an object during horizontal motion is equal to the change in the kinetic energy of the

object – ∆Ek = ½ m (v2 - u2), (Olivier, n.d., a), mass is not the only variable which power

depends on. Furthermore, students infer that if a body is more powerful it will exert a

larger force upon impact than a body less powerful. This again is incorrect, as the cars

exert equal but opposite forces on each other when colliding.

To a lesser extent rational explanations containing misconceptions were evident in

student responses to this question (11%). Some of the students who constructed these

rational explanations held the same common misconception about heavier objects

exerting a greater force. However, they provided a rationale, based on Newton’s

Second Law, for their argument that heavier cars exert a greater force on lighter cars.

For example, a student wrote that:

F=ma. When mass is heavy then F increases or F is more. When mass is light then force is not

that much. A heavy car will exert a greater force on the lighter car than it (lighter car) would on

heavier car and the passengers of the lighter have higher risk of injury.

114

The above response clearly reveals that the student does not realise that F=ma gives

the force needed to accelerate the mass m; it does not give the force exerted by the

mass m on another object. In addition, the student forgets to consider acceleration, the

other variable in Newton’s second law.

Another example of a rational explanation with the same misconception is given in the

following exam-script response:

Fres = ∆p/∆t , as the time for the lighter car to be crashed will be shorter than that of the heavier

car, the force (resultant force) acting on the car will increase quickly and cause more damage

than in a heavier car.

In the above response the student uses Newton’s second law to calculate the force

acting on the lighter car, however, the student makes a mistake. The mistake is that the

student argues that the contact time of the collision is smaller for the lighter car when it

is actually equal to the contact time for the heavier car.

This misconception that heavier cars are more powerful and exert more force on one

another has been reported on in previous studies (Bayraktar, 2009; Eshach, 2010) and

is a result of students viewing the interaction between objects as a struggle where

victory belongs to the stronger, bigger, heavier, or more active object. Students also

construct this misconception because they ascribe the incorrect ontological category to

force, and see it as a property of matter (Galili, as cited by Moore & Harrison, 2004),

much like mass, instead of seeing it as an interaction between two objects (Shymansky

et al., 1997).

4.5.2.2 Second common misconception: total external resistance decreases

when an external resistor connected in parallel is removed

Responses to question 12.3 revealed 394 misconceptions and this represented 13% of

all misconceptions identified. Question 12.3 is shown in figure 4.6 and referred to a

combination of resistors.

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Figure 4.6: An examination question on a circuit diagram of three external resistors


Question 12.3 demanded an explanation for what would happen to the voltmeter

reading should one of the resistors in the parallel combination burn out. The correct

answer to this question is that due to an increase in the external resistance, the current

strength decreases, resulting in a decrease in the internal voltage and an increase in

the voltmeter reading. Fifteen percent of the students in the sample held the common

misconception that the total resistance decreases when the one resistor in parallel

burns out.

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Many students offered genetic explanations containing misconceptions for this question;

39% of the misconceptions identified in this question were exposed in genetic

explanations. Students who constructed genetic explanations offered a variety of

incorrect conceptions as to what would happen when one of the resistors burnt out

without explaining why it would affect the voltmeter reading. The following exam-script

responses are genetic explanations which illustrate the common misconception that the

resistance decreases when a resistor connected in parallel is removed:

Less voltage would be needed since the resistance has dropped.

The reading will increase because more current will pass through without having to go via a

resistor.

The reading at voltmeter v will register a high voltage because the resistor which stops current

from passing through will have burnt out allowing a lot of current to pass.

Students also constructed mechanical explanations for question 12.3; in total 34% of

the misconceptions identified in this question were exposed in mechanical explanations.

Students who constructed mechanical explanations for this question focused primarily

on the resistance of the circuit, thereby exposing the misconception that the total

resistance decreases when a resistor connected in parallel is removed from a circuit.

Examples of such mechanical explanations are given in the following exam-script

responses:

The voltmeter reading will increase, because there is far less resistance within the circuit.

When resistor R is burn out the resistance changes to 13, 5 ohms. Voltmeter reading changes as

there is now less resistance.

Voltmeter it will be more because the less the resistance the higher the voltage.

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Rational explanations which exposed misconceptions constituted 12% of explanations

for this question. Students who constructed rational explanations that revealed,

misconceptions, applied Ohms’ law to determine the change in the voltmeter reading.

The following exam-script responses illustrate such a rational explanation:

If resistor R burns out, the voltage reading will increase. This is because R will increase as there

is no longer parallel resistance. Since V=IR if R increases then the total voltage will also increase

as they are directly proportional.

It will increase because potential difference is directly proportional to resistance.

The above responses are incorrect because although potential difference (V) is directly

proportional to resistance (R), it also depends on the current strength (I) which has

decreased in the situation sketched in this circuit. Also, the students have only

considered the changes in one part of the circuit instead of considering the circuit as a

whole. Cheng and Shipstone (2003, p.193) also found in their study that students tend

to “focus on what happens at only one point in the circuit and forget that they are

dealing with a complex interacting system.”

Four out of the ten students who were interviewed also held the misconception that

resistance decreases when a resistor connected in parallel burns out. The following

excerpt from a student interview further illustrates this misconception:

Researcher: So first tell me if that one burns out, why will there be less resistance in the

circuit?

Student 9: Because there’s one less resistor (smile).

4.5.2.3 Third common misconception: energy is lost

Question 7.5 referred to a hydro-electric power plant where water is funnelled down a

vertical shaft to a turbine below. Question 7.5 is shown in figure 4.7:

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Figure 4.7: An examination question on a hydro-electric power plant


In this question, students were required to explain what happens to the 15% of kinetic

energy that is not converted to electrical energy. The question required a genetic

explanation, because students were expected to state what happens to the kinetic

energy. In total, 13% of the students in the sample incorrectly responded that the

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energy was lost. In the genetic explanations advanced, 126 misconceptions were

identified. This represented 91% of all misconceptions for this question.

Examples of exam-script responses which illustrate this misconception, as revealed in a

genetic explanation, follow:

The 15% of kinetic energy is being lost.

Energy is lost through friction.

Energy is lost as the water falls on the turbine.

In the genetic explanations above, the students focused on what happened to the

energy, thereby exposing the misconception that energy is lost.

Students also constructed this misconception in the interviews. The following interview

dialogue occured when I asked a student to clarify a previous statement that she had

made concerning energy being lost:

Researcher: So you wrote that: “the other 15% is lost through other things such as heat,

movement, sound, etc.” Explain to me more about what you mean when you say

the energy is “lost”.

Student 10: ... the reason I came up with the fact, it could evaporate, it could be lost through

heat, vibrations, it could be lost through a lot of things ...

The above excerpt reflects that this student holds the notion that where the energy is

not being transferred to do work, it is “wasted” or “used up”. Scott et al. (2007, p.49)

explain that since the “concept of energy is used often in everyday contexts and in

everyday social language it is normal to make comments such as ‘I’ve run out of

energy’”. The scientific idea that energy is not used up appears to be far-fetched in

relation to everyday ways of thinking and speaking. Another student interviewee,

student three, confirmed that it is difficult to understand that energy is not lost by stating

the following:

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So in all essence it is lost, but the energy still is there it just isn’t in your possession, … they try

and steer us away from the term that it is lost, they try to tell us that it is not lost, it is just

converted and so forth, but for me to use, like, layman’s terms and to explain the science behind

it, to understand it better, I try to explain it in things that are easy to understand, like lost and not

converted.

In the above excerpt the student explains that the energy is still there but that it just isn’t

in your possession and that he prefers to explain things using words that are easy to

understand. This comment may illustrate that students which claim that “energy is lost”

do not necessarily hold a misconception regarding the conservation of energy but that

they may just use the phrase as a figure of speech. According to Harrison at al. (1999,

p.68) it is not uncommon for students to struggle with “adopting scientific understanding

and its associated language.” This is especially the case with scientific terminology such

as “energy” which is used differently in everyday language.

4.5.2.4 Fourth common misconception: a split-ring is found in an AC generator

In question 13.1 students were asked to identify the type of generator that was depicted

and to provide a reason for this classification. Question 13 is shown below in figure 4.8:

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Figure 4.8: An examination question on a generator


This question required a genetic explanation as students needed to identify what type of

generator was depicted on the basis of what components it consisted of. Most of the

students holding misconceptions regarding the AC generator offered genetic

explanations (87%). By constructing genetic explanations, students focussed on what

components the generator had, thereby revealing that 8% of the sample held the

misconception that an AC generator has split rings. Exam-script responses illustrating

this misconception are quoted below:

AC generator, because of the presence of the split rings.

AC generator because it uses split rings.

Alternating current (AC); it has two split rings and moves anti-clockwise.

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Clearly these students are confused regarding the difference in the working of slip rings,

which enables an AC current to flow in a generator, and a split-ring commutator which

enables a DC current to flow in a generator and which is also used in a motor. Olivier

(n.d., p.200, 202) explains that “ the alternating current generator has two slip-rings” and

“For a direct current generator (dynamo) which generates direct current instead of

alternating current, we can replace the slip-rings with a split-ring commutator (as used

by the dc electric motor).”

4.5.2.5 Fifth common misconception: the voltage increases when appliances

are added to a multi-plug

In question 14.3 students were asked to apply Physics principles to explain why a cut-

off switch is important in a multi-plug that has many appliances connected to it. In

answering this question, students needed to explain that as more appliances (resistors)

are connected in parallel, the total resistance in the circuit decreases, the current

increases and the components get hot unless the cut-off switch acts as a circuit

breaker. The question required a rational explanation, but a significant number of

students offered functional and genetic explanations instead. Overall students’

responses to this question yielded 16% of all identified misconceptions. Question 14.3 is

shown in figure 4.9:

Figure 4.9: An examination question on a cut-off switch


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There were 324 cases of misconceptions in the functional explanations offered by

students and this represented 69% of all misconceptions for this question. The students

who constructed these functional explanations revealed a variety of misconceptions

regarding the function and operation of a cut-off switch. A common misconception in

this type of explanation was that a cut-off switch lowers the voltage, which starts to

increase as more appliances are connected to the multi-plug. Six percent of the

students in the sample held this misconception. The idea that the voltage increases as

resistors are added in parallel is incorrect because it is the current which surges and not

the voltage. This misconception is illustrated in the following exam-script responses:

The cut-off switch reduced the build up of energy transferred to appliances to reduce heat so that

appliances can receive required energy and they cannot burn easily. The cut-off switch reduces

the high voltage in the electric equipment to reduce damage of appliances.

When you are using a multi-plug you are stepping down the voltage and saving electricity at the

same time.

It is important to have a cut off switch because-the voltage inside the plugs could build up

immensely if not used – the heat inside the wire and therefore valuable energy is lost.

Students also constructed other misconceptions regarding the multi-plug which are

discussed later in this chapter, this was probably due to the fact that many students are

not well acquainted with a cut-off switch and how it works in relation to the multi-plug.

Student interviewee nine clarified this by saying: “I didn’t have an idea what a cut-off

switch is.” This same student also illustrated the difficulty that many students have with

using scientific language consistently:

Student 9: Well, too many plugs using too much energy, electricity…maybe if you use

different machines or things that use a lot of power, and so it has happened

before in our house that the plug just wanted to blow up, because it was too much

friction or .. I don’t know? Power.

Researcher: What do you mean by power?

Student 9: Electricity.

Researcher: Electricity. What do you mean by electricity?

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Student 9: The flow of electrons.

Clearly this student is confused about the meanings of the concepts, energy, power,

electricity and current, hence the inconsistent use of these concepts. Research has

found that students use the terms energy, current, power, electricity, charge, electrical

potential, potential difference, emf and voltage synonymously (Bull et al., 2010; Cheng

& Shipstone, 2003; Periago & Bohigas, 2005; Shipstone in Driver et al., 1985). Moore

and Harrison (2004) argue that this is largely due to a lack of understanding of abstract

concepts.

4.6 OTHER MISCONCEPTIONS

Other than the five common misconceptions that occurred most frequently in the

student responses, this study revealed additional misconceptions. These other

misconceptions are discussed in this section.

4.6.1 Forces acting on two separate interacting bodies can be added, and may

add up to zero causing the bodies to remain stationary

The misconception that forces acting on two separate bodies can be added, and may

add up to zero, causing the bodies to remain stationary, was exposed in the following

interview response:

Researcher: You also wrote that the fact that the stationary car moved also indicates a greater

force by the heavier car, do you think that it is always like that, that the object that

moves is experiencing a bigger force?

Student 1: Yes, cause, I think so, because if like the um the force was the same then it

wouldn’t have moved at all like if you try and push a wall your force is not big

enough so it is not going to move at all.

In the above response to question 5.3 of the Physics exam, the student constructs a

rational explanation by applying Newton’s first law. Although the student does not

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directly refer to Newton’s first law, the student reasons that the lighter car started

moving because it was pushed harder, in other words was acted upon by a resultant

force. The student is correct in arguing that the lighter car started moving as a result of

a resultant force. However, the resultant force acting on the lighter car is not the sum of

the two forces that the two cars exert on one another, but rather the sum of all the

forces acting on the lighter car. According to Olivier (n.d., b) Newton third law force pairs

act on two different objects and can therefore not cancel each other out. The

misconception that forces of interaction acting on two objects can be added together is

a common misconception previously reported on by Halloun (1998). The above

response is also incorrect in asserting that objects do not move when exerting equal

forces on one another. Interacting objects always exert equal opposite forces on one

another and in many cases the objects may accelerate. The acceleration of an object is

not determined by the force that it exerts on another object, but rather by the forces that

are acting on it.

4.6.2 Light objects have less momentum and experience a greater change in

momentum during a collision

The misconception that light objects have less momentum and experience a greater

change in momentum during a collision was exposed in the following pre-interview test

response and interview response by student interviewee three:

The light object has little momentum and when it collides with a heavy object momentum is

transferred between them. The light object with the large momentum will now move at a higher

velocity, so the impulse of such a collision will be also more on a lighter object.

Because the impulse is like the change in, the change in momentum, from like before, and a light

car will have low momentum before it crashes and then when it does crash the, the, like energy

which is transferred between the two vehicles will increase its momentum and it will like, the

shock will be large, like the people on the inside will feel like a big force backward and their necks

will hurt or break or whatever, so the impulse, the change in momentum will like be larger.

In the above responses to question 5.3 the student constructed mechanical

explanations which focus on the momentum of the lighter car. In focussing on the

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momentum, the student exposed misconceptions regarding momentum. Lighter objects

do not always have less momentum, because momentum depends on both mass and

velocity. In this case the lighter car would have zero momentum before the collision

because it was stationary. The student continued by arguing that momentum is then

transferred and the lighter car experiences a greater change in momentum. It is

incorrect to deduce that the lighter car experiences a greater change in momentum,

because according to Newton’s third law the impulse experienced by both cars is equal

but opposite in direction (Heyns, 1999).

4.6.3 Momentum is lost or converted into heat or some other form of energy and

kinetic energy and momentum is the same property of motion

The misconception that momentum is lost or converted into heat or some other form of

energy is illustrated by the following student interviewee response:

Researcher: And you wrote: "Momentum won’t be conserved as the car’s shape will be

permanently changed", explain why you think the momentum isn’t conserved

when that happened?

Student 5: ..Umm, because if it was conserved then the momentum after the collision will

still be equal to the momentum before the collision, and obviously because there

is change in form and heat and whatever, then obviously momentum was lost.

In the above response to question 5.2 the student constructed a genetic explanation by

focussing on what happens instead of providing scientific evidence. By focussing on

what happens, the student reveals the misconception that momentum is lost or

converted into other forms of energy. Clearly, this student is confused between kinetic

energy and momentum and is using the terms as if they have the same meaning, thus

exposing another misconception that kinetic energy and momentum is the same thing.

Previous studies have also reported on the occurrence of the misconception that kinetic

energy and momentum is the same thing (Bryce & MacMillan, 2009; Lin, 1983). These

two quantities of mass in motion appear to be similar because they both incorporate

both mass and velocity.

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4.6.4 Misconceptions concerning the internal voltage of a battery

Two misconceptions about the internal voltage of a battery became evident in this

study. Firstly, students hold the misconception that a voltmeter measures the internal

voltage of the battery when it is connected across the battery in a closed circuit.

Secondly, students hold the misconception that the internal voltage of a battery is not

affected by changes in the external circuit. These misconceptions are illustrated by the

following exam-script responses to question 12.3:

The reading on the voltmeter will remain the same because the voltmeter is attached across the

battery and not the resistor. It will not be affected because the battery does not change.

Voltmeter will remain unchanged because it only measures the potential difference across the

cell.

It will remain the same because it is connected across the internal resistance and the internal

resistance stays the same.

The first two quotations above represent genetic explanations because the students

focus on what is happening. They argue that the voltmeter reading remains the same

because it is measuring the potential difference across the battery which remains the

same, thereby incorrectly implying that the voltmeter is measuring the internal voltage

which remains the same. The last quotation above represents a mechanical explanation

as the student focuses on the resistance of the battery. The student argues that since

the internal resistance of the battery stays the same, the voltmeter reading stays the

same. The student supplies no rationale as to why the constant internal resistance

leads to a constant potential difference across the battery. It seems that this student

holds the same misconception that the voltmeter is reading the internal voltage of the

battery and that the internal voltage remains unchanged by the external changes. This

misconception is incorrect because a voltmeter connected across a battery in a closed

circuit measures the terminal potential difference which is the potential difference of the

external circuit (Heyns, 1999). In addition, the internal voltage of the battery is not

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constant; it varies as the current strength varies and also as the internal resistance

varies due to slight changes in the temperature of the battery. This misconception that

the internal voltage of the battery remains unaffected by changes in the external circuit,

illustrates how students forget that they are dealing with a connected circuit (Cheng &

Shipstone, 2003).

4.6.5 The potential difference across resistors connected in parallel remains

constant when one of the resistors is removed

The misconception that the potential difference remains constant when one of the

resistors connected in parallel is removed is illustrated by the following exam-script

responses:

The reading will not change. In a parallel circuit, the voltmeter reading stays the same for all

resistors. Therefore removing one (resistor) will not change it.

It will remain the same because it is connected in parallel and parallel circuits are current dividers

and not potential dividers.

In the above responses to question 12.3, students constructed rational explanations by

applying the scientific principle that when resistors are connected in parallel the

potential difference across the parallel combination is equal to that across each of the

individual resistors (Heyns, 1999). While the principle is correct, students appear to

have overextended the principle by arguing that the potential difference across the

parallel resistors remains the same even when one of the resistors burn out.

4.6.6 DC motors and generators have slip rings and motors and generators are

the same type of machine

The misconceptions that dc motors and generators have slip rings and that motors and

generators are the same type of machine, are illustrated by the following exam-script

responses to question 13.1:

A DC generator. There are slip rings used.

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DC motor, there is a direct current flowing to the coil and there are two slip ring indicating that this

is a DC motor.

Motor generator because of it uses motors to generate it fields and it is accumulated a lot and in

magnetism.

It is the motor generator because it has the x and y.

Students may be confused about the differences between motors and generators due to

their similar structure and components. It is important for teachers to emphasise that

“motors use electrical energy to produce mechanical energy” and that “generators use

mechanical energy to produce electrical energy” (Olivier, n.d., a, p.200).

The following excerpt from an interview also illustrates the confusion between slip rings

and a split ring and between motors and generators:

Researcher: In your worksheet you wrote that: “this generator is a dc generator, because of its

slip rings.” Tell me more about the difference between an ac and a dc generator.

Student 4: Ok, I don’t know. Um, ac, am I right, ac generators, ………….…, dc generators

use electricity to create mechanical energy, I think, and ac generators, …, yah,

use mechanical energy to create energy, I think, I am not sure, cough, so what I

think mam, is that because an ac generator is slip ring and a dc one is, no a dc

one is slip rings and an ac one is split rings, that’s what I mean.

Researcher: Would you say these in the diagram are spilt rings or slip rings?

Student 4: Slip.

Researcher: Have you done an experiment in the class, where you have built one or have you

seen an ac or dc generator?

Student 4: Experiment no; it’s what I saw from the textbook.

The above excerpt also illustrates the fact that students often do not get to do the

practical linked directly to the work. In the teacher interviews, teacher two confirmed that

although “the kids are visually stimulated”, and practicals can “have a HUGE impact”,

“due to the big class ... and expensive equipment, you can’t always let everybody do his

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own experiment” and “if you had enough time…and enough resources” it would be

easier to do practicals. Even so, Ausubel (in Novak, 2004, p.32) maintains that

“students require concrete-empirical props to develop abstract concepts.”

4.6.7 A cut- off switch works just like a normal switch, it can be switched off to

save electricity

The misconception that a cut- off switch works just like a normal switch is illustrated by

the following exam-script responses:

We need switch so we can switch on and off any time we need to switch.

It is important because you can switch off the unused plugs in order to save electricity.

A cut-off switch is also important to save energy as additional energy which is not required will not

be use.

The above responses are all functional explanations that focus on the function of a cut-

off switch thereby exposing the misconception that a cut-off switch works like a normal

switch. These responses are incorrect because a cut-off switch is not like any other

switch that you can switch on or off. A cut-off switch is a trip-switch that automatically

breaks the circuit when the current is dangerously high.

4.6.8 Household appliances such as those connected to a multi-plug are

connected in series

The misconception that household appliances such as those connected to a multi-plug

are connected in series is illustrated by the following exchange that took place during a

student interview:

Researcher: What makes the current high?

Student 7: If you use too many appliances like them all in one socket.

Researcher: Why should that cause the current to increase?

Student 7: It needs to be more places at once.

Researcher: What do you mean by this?

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Student 7: There is now a lot of them together

Researcher: Are the appliances connected in series or parallel?

Student 7: Probably series

Researcher: Why do you say so?

Student 7: Because if one appliance breaks the other will still keep going.

In the exchange above, the student focuses on the physical connection of the multi-

plug, thereby presenting a mechanical explanation which reveals the misconception that

household appliances are connected in series. Although the student correctly relates

that the current will increase as more appliances are connected to the multi-plug, the

foundation to this assertion is flawed as the student believes this increase to be due to a

series connection of appliances. Seven of the students interviewed believed that the

appliances were connected in series. Pilatou and Stavridou (2004) found in their

research with primary school children that even though they handle many household

electric appliances every day they do not know that the electric installation in a house is

a parallel connection. They argued that it is because students “cannot observe the route

they follow behind the sockets” (Pilatou & Stavridou, 2004, p.698).

4.7 INTERPRETATION OF THE RESULTS REGARDING POSSIBLE SOURCES

OF MISCONCEPTIONS

In this section I will interpret what student explanations revealed about possible sources

of student misconceptions. I will discuss the individual, social interactions, language,

assessment and context as possible sources of misconceptions, as well as the

relationship between these factors.

4.7.1 The individual as a source of misconceptions

Observation, experience and understanding are influenced by an individual’s prior

beliefs and knowledge (Carr et al., 1994; Strike, 1983). In everyday life students

observe what happens in various situations and then construct explanations in terms of

their own beliefs and misconceptions, hence their inclination to offer genetic

explanations. The tendency to describe what is happening instead of why it is

happening was most prevalent in this study. In total, 41% of the misconceptions found

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in this study were found in genetic explanations. An example of such a misconception is

illustrated by the following response: “The cut-off switch disables the flow of electricity

when not in use" to the question: “Using principles in Physics, explain clearly why this

cut-off switch is important.”

Students are also accustomed to observing the physical features of objects, hence their

inclination to offer mechanical explanations of phenomena by only providing evidence in

terms of an object’s physical features. Mechanical misconceptions were also highly

prevalent in this study (37%), indicating that students are not in the habit of supplying

laws of Physical Sciences as evidence for phenomena and rely on the type of

mechanical reasoning that is used in everyday life. This is especially the case when

students are asked to explain a phenomenon set in an everyday context. Hence, the

construction of misconceptions such as “heavier cars exert more impact on lighter cars

during a collision” as illustrated by this response: “A lighter car will easily get crushed

due to the mass of the heavier. The heavier the mass, the greater the force.” It is clear

from the examples of mechanical explanations provided in this study that students tend

to focus on the observable physical properties of objects. When students do this they

may expose misconceptions about the physical properties of objects and the effect

these properties have on certain situations.

4.7.2 Social interactions as a source of misconceptions

Although students construct their own explanations and conceptions in order to make

sense of their experiences and observations, these constructions are socially

negotiated. According to the theory of social constructivism, knowledge is attained,

developed and validated through social interactions (Kibuka-Sebitosi, 2007; Matthews,

1998). Hence, a second source of misconceptions is the interaction between students

and various social role-players such as teachers.

In this study I found that teachers and textbook writers in trying to simplify matters

construct explanations which may be misinterpreted by students. For example, students

are taught that total linear momentum is conserved during collisions and explosions in

closed systems. This statement may cause students to construct the misconception that

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momentum is not conserved in open systems, and that it is somehow converted to

something else or lost, like energy. The following student response, by student

interviewee five illustrates this misconception:

If it was conserved then the momentum after the collision will still be equal to the momentum

before the collision, and obviously because there is change in form and heat and whatever, then

obviously momentum was lost.

The above response is a genetic explanation which focuses on what happens, thereby

exposing a misconception about what happens in an open system. In order to prevent

this misconception, teachers need to explain that when objects collide or explode the

momentum that is transferred from one object to another does not only result in the

displacement of that object as a whole, but that it also increases the momentum of the

particles in the object which can then move within that object. For example, when a car

crumples up upon impact, some of the momentum that is transferred is used for linear

translational motion and some increases the momentum of the car’s particles. The

increase in internal momentum of the car’s particles results in the car changing shape. It

is also important for teachers to emphasise that not only is momentum also transferred

and used for internal motion of the particles within an object, but that momentum is also

transferred between the colliding bodies and the surface, air and objects inside of the

colliding bodies. Working with closed systems limits the number of objects that are

involved in the transferral of momentum, but total momentum still remains constant in

an open system. Explaining the conditions set by Physical Sciences is vital as it enables

students to understand how Physical Sciences are applied to the real world (Bryce &

MacMillan, 2009).

Teachers may also cause student misconceptions by using anthropomorphic

explanations to simplify abstract theories. For example, teachers may attempt to

illustrate the concept of electrical current by explaining that electrons choose the path of

least resistance. Although Treagust and Harrison (2000, p.1165) argue that

anthropomorphisms are “acceptable elements of effective pedagogical content

explanations” and that they enable students to relate to abstract concepts,

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anthropomorphisms may cause students to believe that inanimate particles really do

have human attributes. Few of the student responses analysed in this study could be

classified as anthropomorphic explanations, nevertheless, the following exam-script

response illustrates how students may construct anthropomorphic misconceptions: "So

that electrons would get time to rest, when switch it on they perform a good work."

Teachers may also cause misconceptions by teaching the relationship between

variables and the calculation of variables without spending enough time on developing

students’ conceptual understanding of the variables found in scientific laws. This may

lead to the misconception that the various variables in a scientific relationship are all the

same thing. This is illustrated by the following response by student interviewee nine:

Well, too many plugs using too much energy, electricity…maybe if you use different..machines or

things that use a lot of power, and so it has happened before in our house that the plug just

wanted to blow up, because it was too much friction or .. I don’t know? Power.

The following response by the first teacher that was interviewed also illustrates how

important it is to develop conceptual understanding of the basic concepts in order to

prevent misconceptions:

I would say improper preparation before hand. That you just fire away. That you teach them

something for which you did not really prepare the basic concepts enough. In Science very often

they come and they have no basic concepts and you fire away like with electricity and they have

no idea really.

Teachers are not the only social role-players who may cause misconceptions, society in

general and social language also affects the construction of misconceptions. This effect

is discussed in greater detail in the next section.

4.7.3 Language as a source of misconceptions

The construction of knowledge is influenced by language. How students interpret new

information and link it to their preconceptions is influenced by how well they understand

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the language used by their teachers, peers or textbooks. Students’ understanding is

also influenced and reinforced by their own ability to articulate their understanding

(Sawyer, as cited by Berland & Reiser, 2008). Hence, students with a poor command of

language construct misconceptions as a result of not being able to understand the

learning material. In this study I classified many student responses as inconclusive in

terms of misconceptions because the language used was so poor that it was not clear

whether the student held a misconception or not. Many of the students who wrote this

exam were writing it in their second language, which explains why their command of

English is so poor. The following exam-script response, to a question that required

principles of Physics as evidence, illustrates the problem that many students have with

the use of language: “Because the traffic officer always he/she see the accident of many

cars.” The teachers that I interviewed also explained that: “I still think that there is a

language thing involved because they, they just do not sometimes understand what you

are explaining to them” and “the reading level that is a big problem with some of our

students.”

Students’ grasp of social language is not the only dimension of the effect that poor

language has on the formation of misconceptions. Lemke, cited by Scott et al. (2007,

p.46), explains that “learning science involves learning to talk science.” Students who do

not understand scientific language will struggle to understand Physical Sciences and

may construct misconceptions based on their misunderstanding of scientific

terminology. Misconceptions revealed in this study, such as “energy, voltage, electricity,

current, and power are the same thing” originate because students do not understand

scientific language. The incongruence between scientific language and everyday

language is another source of misconceptions. Often words do not have the same

meaning in scientific language as what they do in everyday language and this causes

misconceptions. Examples of such misconceptions revealed in this study are: mass is

the same as weight and energy is lost. In everyday language weight is regularly used as

a synonym for mass and social media often advertises weight loss products. Physical

Sciences, however, clearly differentiates between mass and weight. In everyday

language it is also acceptable to speak of lost energy; modern society continually

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emphasises the need to save energy as if we are destroying it. Scientists, however,

explain that energy cannot be destroyed and that the problem actually is that we are

transporting, transforming and degrading energy into forms that we are as yet unable to

exploit. The incongruence of everyday language and scientific language as a source of

misconceptions is illustrated by the following student interview response, by student

three:

They try to tell us that it is not lost, it is just converted and so forth, but for me to use, like,

layman’s terms and to explain the science behind it, to understand it better, I try to explain it in

things that are easy to understand, like lost and not converted.

Scientific language not only differs from social language in terms of the meaning of

certain terms, it also includes a host of symbols that are not used in social language and

that must be mastered by students. In the next section, on assessment as a possible

cause of misconceptions, I will discuss how an over-emphasis of the manipulation of

these symbols causes misconceptions about their meaning.

4.7.4 Assessment as a source of misconceptions

Assessment, in the subject-field of Physics, places a significant emphasis on exemplar-

type calculation questions. The 2008 NSC Physics exam paper consists of 21%

explanation-type questions and 79% non-explanation-type questions. In order to meet

performance expectations teachers teach to the test by training students to answer

calculation-type questions. This training leaves teachers with almost no time for

engaging in deeper conceptual development and thus assessment becomes an indirect

source of misconceptions. The following response by student interviewee ten illustrates

the emphasis on exemplar-type calculation questions:

You know going through papers it’s more like these days you just get the same questions and

then, you like, kind of like store it in your head, we don’t really sometimes understand what’s

happening and what… what’s going on we just store it.

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In addition, exemplar-type calculation questions often assess scientific knowledge in a

fragmented decontextualised manner. In other words, each scientific principle or law is

assessed separately, thereby creating the impression that each law applies only to

certain situations. Also, the situations sketched in assessment questions seem artificial

because certain contextual features are omitted. This creates the impression that

Science does not apply to real-life situations. The effect that context has on the

formation of misconceptions is discussed in greater detail in the next section.

4.7.5 Context as a source of misconceptions

In order to improve on the decontextualised nature of traditional assessment,

contemporary assessment questions require the application of knowledge to everyday-

life situations. However, because students are accustomed to making sense of their

experiences and observations in terms of their pre-knowledge, which includes

misconceptions, exam questions set in everyday-life situations prompt students to apply

their pre-knowledge and not their scientific knowledge. In the exam analysed in this

study, students were asked to apply their scientific knowledge to everyday contexts

such as a traffic officer observing the damage at an accident scene. The familiar

accident scene prompted students to use their preconceptions regarding the interaction

between two objects, thereby exposing the misconception that heavier objects exert a

greater force on lighter objects, than what lighter objects exert on heavier objects. This

misconception is illustrated by the following student response: “The statement by the

traffic officer is correct because the passenger in a heavier car has weight and the

material of the car has a higher mass and its velocity is also high which means the car

is very strong, as for the lighter car it is not strong.”

Question 14.3 of the Physics exam was also set in an everyday-life context. The context

in this question was the overloading of a multi-plug. Many students seemed to be

familiar with the overloading of a multi-plug and were prompted to use their

preconceptions about how a multi-plug functions. This exposed the misconception that

the overloading of a multi-plug is dangerous because it causes the voltage to increase.

The structure of the multi-plug and the function of the cut-off switch, however, seemed

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to be unfamiliar to many students. Student interviewee nine explained that “I didn’t have

an idea what a cut-off switch is.” Students needed to be aware that the structure of the

multi-plug is such that the appliances are connected in parallel to a multi-plug. This was

necessary so that they could deduce that the current would increase as more

appliances were connected to the multi-plug. During the student interviews conducted in

this study, it became evident that students are not familiar with the connection of

household appliances and that they hold the misconception that household appliances,

such as those connected to a multi-plug, are connected in series. Many students that

were unfamiliar with the cut-off switch likened it to a normal switch that can be switched

on or off. They then proceeded to construct the misconception that a cut-off switch can

be switched on or off in order to save electricity. This illustrates how students may

construct a misconception by connecting an unfamiliar context with a familiar one. It

seems that although it is important for students to be able to apply their knowledge, the

use of everyday contexts may be confusing, especially when students are not familiar

with the everyday context used in examinations. During an interview teacher one

commented that students “just sometimes do not understand what you are explaining to

them, because it’s not in their world, we take it that they all have experience and that

they all read and that they all have general knowledge, and these days they have very

little general knowledge.” When students have not used, explored or learned about

physical objects such as a cut-off switch, then these objects and the manner in which

they function do not form part of students’ conceptual frameworks even if these objects

can be found in their homes.

Students also construct misconceptions by applying ideas, which are valid in some

contexts, to contexts where they are invalid. In question 12.3, of the Physics

examination which forms part of this study, a resistor connected in parallel burns out

and students are required to predict the effect of this change on the voltmeter reading.

Some students responded by arguing that the voltmeter reading would change as a

result of an increase in the total current running through the circuit caused by the

resistor burning out. Although it is true that for resistors in series the removal of one

resistor leads to a decrease in resistance and an increase in current, when resistors are

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connected in parallel the removal of a resistor leads to an increase in the resistance and

a decrease in the current.

Students may also create a separate context of application for scientific knowledge

when it does not match their ideas. As a result, misconceptions and scientific

knowledge co-exist within students’ conceptual frameworks, each within their own

separate context (Klassen, 2006; Tytler, 1998). This was evident in students’ responses

to question 5.3. Although the context in question 5.3, the accident scene, is a familiar

everyday-life context which prompts students’ preconceptions, it is also a context often

used in Physics textbooks. Therefore, some students realised that the question

demanded the application of scientific principles such as Newton’s third law. However,

since some of these students also held misconceptions contradicting Newton’s third

law, they constructed a separate context of application for Newton’s third law. This is

illustrated in the following response by student interviewee one:

... because if like the um the force was the same then it wouldn’t have moved at all like if you try

and push a wall your force is not big enough so it is not going to move at all.

The above response illustrates how a student can confine the context of application of

Newton’s third law to situations where the objects do not move. Students who believe

that heavier objects exert a greater force, may alternatively confine the context of

application for Newton’s third law to the interaction between objects of equal mass and

strength. In the responses to question 5.3 some students even applied both Newton’s

third law and their contradicting misconceptions in one explanation, as illustrated below:

Using Newton's third law the car with a heavier mass will exert a greater force on the car with a

lighter mass.

This response illustrates how scientific principles can be loosely assimilated within the

conceptual framework of students, without proper conceptual understanding.

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In this section I reported that everyday-life contextual questions prompt students to

apply their misconceptions instead of scientific knowledge. I also discussed how

students create separate contexts of application for their misconceptions and scientific

knowledge, thereby allowing both to co-exist within their contextual frameworks and

creating misconceptions about the range of application of scientific knowledge. The

discussion in this section also illustrated how misconceptions are constructed when

students over-extend the range of application of scientific knowledge to a context where

it is not valid.

4.7.6 Graphical representation of the possible sources of misconceptions and

their link with misconceptions

In order to clarify the possible sources of misconceptions I constructed the following

concept map as shown in figure 4.10:

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Misconceptions

Hidden or

Figure 4.10: A concept map illustrating the relationship between

misconceptions and the causes of misconceptions


Exposed:

Complex

or

Incomplete

or

Simple

Non-

response

8, 6%

Responses

with poor

language

Individual

person

Everyday

Language

Vs

Scientific

Language

Assessment emphasises calculation-

type questions and fragments

knowledge

Society:

Teachers

Family

Peers Everyday Context

Vs Science

Exemplar Context

Interaction Co

nstru

cts

Co-construct

Ca

use

s

Causes

Use

bo

th in

co

nsis

ten

tly

Influences Influences

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The concept map indicates the various causes of misconceptions. These causes

include both individuals and society who co-construct misconceptions. Misconceptions

are also caused because individuals together with society use scientific language and

everyday language interchangeably, despite there often being differences between

them which may lead to misconceptions. Society also influences assessement trends

which in turn influences teaching strategies and may cause student misconceptions.

The introduction of everyday contextual questions into assessment also influences

student misconceptions as the context cues the use of preconceptions held by students.

Exemplar-type questions often ignore certain everyday-life conditions which creates the

misconception that Science does not apply to the real world.

In the concept map I also classified misconceptions as either exposed or hidden. I

presented the relationship between exposed misconceptions by placing them in a

hierarchy. I placed complex rational constructs at the top of the hierarchy, because

students that had constructed rational misconceptions had applied scientific concepts

and theories in these constructions, albeit incorrectly. The main cause of these complex

misconceptions is the poor understanding of the relationships between variables in the

basic laws of Physical Sciences.

I classified the misconceptions found in mechanical, genetic, functional, teleological and

practical explanations as “incomplete constructs” and placed them below complex

rational misconceptions in the hierarchy of misconceptions. I placed them lower in the

hierarchy because students referred only to physical properties, functions and

phenomena in a fragmented manner instead of referring to scientific theories as

evidence in their explanations. I classified them as incomplete because during student

interviews I found that students who initially gave mechanical explanations provided

rational explanations upon probing. This shows that students do not realise what

explanation-type questions expect from them, don’t always have enough time to

construct rational explanations and do not have experience in constructing rational

explanations.

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I classified misconceptions found in analogical, anthropomorphic and metaphysical

explanations as “simple constructs” and placed them below the incomplete constructs in

the hierarchy of misconceptions. I did this because students who create simple

constructs explain occurrences by relating them to other things from their everyday

experiences, rather than by applying scientific concepts to explain the occurrence.

Lastly, I classified the misconceptions found in tautological explanations, those

explanations classified as inconclusive in terms of the types of explanations, and the “no

responses” as hidden misconceptions. I did this because students who responded in

these ways did not reveal whether or not they held any misconceptions.

4.8 CONCLUSION

In this chapter, data regarding the performance of students in explanation-type

questions and the frequency of misconceptions revealed in various explanation-types

was presented. Data illustrating these misconception-types as well as specific student

misconceptions were also discussed. The chapter ended with an interpretation of what

misconception-types reveal in terms of possible sources of misconceptions. In the final

chapter the findings are summarised and possible recommendations are made on

addressing misconceptions and the performance of students in explanation-type

questions.

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CHAPTER 5

SUMMARY, RECOMMENDATIONS AND CONCLUSIONS

5.1. INTRODUCTION

This study analysed the explanations of students found in their responses to questions

in the 2008 NSC Physics examination. Previous studies I have already referred to have

investigated student misconceptions on specific topics in Physical Sciences through

student interviews. In this study I have reported on a large scale project which involved

the analysis of 921 examination scripts, focussing on student explanations to questions

on a range of Physics topics. I sought to understand the nature of the misconceptions

evident in these explanations by firstly identifying characteristics of the explanations. In

my analysis I used a framework developed by Dagher and Cossman that they employed

for verbal explanations in a Physical Sciences class. I found this framework to be

effective as it enabled me not only to identify specific misconceptions but also to classify

these misconceptions based on characteristics of the explanation offered. I believe that

this method of analysis does offer researchers a reliable and efficient way by which

written student explanations can be probed for misconceptions.

Nevertheless, delving into written student’ explanations for misconceptions remains a

complex task. Students often construct brief off the cuff responses or poorly articulated

responses, hardly giving one a glimpse of their understanding. This is especially the

case during formal assessments where students have a limited time to express

themselves. It is therefore important to further investigate the characteristics of

misconceptions exposed through written explanations. I have done this by conducting

both student and teacher interviews. The content analysis of student’ explanations

documented in both written exam scripts and interview transcripts has enabled me to

find answers to the following research questions which I formulated at the beginning of

this study:

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(1) What are the common student misconceptions that are revealed in a high

stakes Physics examination?

(2) How do students perform in explanation-type questions?

(3) What do explanation-types reveal about student misconceptions?

This chapter reports on the key findings of the study, discusses the implications for

teachers and other role-players in education, critiques the study, and also makes

recommendations for future studies.

5.2. SUMMARY OF MAJOR FINDINGS

In this section the main findings that were constructed through the analysis of the data

will be reviewed.

5.2.1 Common misconceptions in Physics

Through an analysis of the content of student’ explanations and the types of

explanations offered by students, I discovered specific misconceptions held by students.

The following misconceptions regarding mechanics were exposed:

• heavier/stronger cars exert more impact on lighter/weaker cars during a collision;

• mass, weight, force, power, and strength is the same thing;

• weight and force are properties of an object, just like mass;

• forces acting on two separate interacting bodies can be added, and may add up

to zero, causing the bodies to remain stationary;

• Newton’s third law only applies to closed systems;

• light objects have less momentum;

• light objects experience a greater change in momentum during a collision;

• momentum is lost or converted into heat or some other form of energy;

• kinetic energy and momentum is the same thing;

• energy is lost.

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I also discovered the following student’ misconceptions regarding electricity:

• total external resistance decreases when an external resistor connected in

parallel is removed;

• changes in the external circuit have no effect on the internal voltage of the

battery;

• a voltmeter connected across a battery in a closed circuit measures the internal

voltage of the battery or the emf of the battery;

• the potential difference across resistors connected in parallel remains constant

when one of the resistors is removed, because parallel resistors are not voltage

dividers;

• a split-ring is found in an AC generator;

• slip rings are found in DC motors and generators;

• generators are the same as motors;

• the voltage increases when appliances are added to a multi-plug;

• energy, voltage, electricity, current, and power is the same thing;

• a cut-off switch saves electricity by cutting off the flow of electricity to appliances

which are off but are still drawing small currents;

• a cut-off switch works just like a normal switch, it can be switched off to save

electricity or to prevent a fire;

• household appliances such as those connected to a multi-plug are connected in

series.

5.2.2 Student performance in explanation-type questions

The sample of 921 students achieved an average of 17, 4% percent for the explanation-

type questions. They performed 8,4% better in the non-explanation-type questions.

These findings are in line with previous studies that have shown that students perform

“particularly badly in questions which require them to give qualitative responses” (Bryce

& MacMillan, 2009, p.740). Also, despite the fact that misconceptions are not always

exposed by student explanations, a significant number (27,4%) of student explanations

did expose misconceptions.

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The poor performance of students in explanation-type questions may be attributed to

the fact that explanation-type questions are more likely to expose the misunderstanding

of students. Students are trained to rote-learn calculation-type questions in preparation

for examinations, thereby enabling them to provide the correct answer for such

questions without exposing their misconceptions. Rote learning of calculation-type

questions is advanced by examiners who emphasise non-explanation-type questions.

Non-explanation-type questions constituted 79% of the 2008 NSC Physics examination.

Since calculation-type questions are emphasised in high stake examinations, teachers

spend many hours training their students to answer these types of questions. This

leaves teachers very little time to develop the conceptual understanding of their

students.

It is also important to remember that although this study focused on explanation-type

questions, misconceptions affect student performance in other question-types as well.

The sample of students investigated in this study achieved an overall average of 24%

for the 2008 NSC Physics examination which is comparable to the average of less than

30% achieved by 45% of the entire group of students who wrote the Physical Sciences

examination.

5.2.3 What explanation-types reveal about misconceptions

The types of explanations constructed by students holding misconceptions reveal

information about both the nature of misconceptions as well as the source of the

misconception. This is discussed next.

5.2.3.1 Explanation-types reveal the nature of misconceptions

The most prevalent cases of misconceptions were found in genetic (41%) and

mechanical (37%) explanations. It became clear from the analysis of the explanations in

the examinations scripts and the interviews that students have a naïve, superficial and

fragmentary understanding of scientific phenomena that is based upon their

misconceptions. These misconceptions are not theoretically grounded, as students use

the contextual features of the problem situation as evidence for their misconceptions.

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This finding correlates well with other studies that allude to the context dependency of

students’ reasoning, found amongst students entering higher-level education (Hammer,

2000; Hamza & Wickman, 2008; Knight, 2002). When assessment questions test the

ability of students to apply knowledge to everyday scenarios, a particular problem

context activates a particular alternative conception (Clough & Driver, 1986; Driver et

al., 1985; Palmer, 2001), steeped in everyday language (Tytler, 1998). This was also

evident to a large extent in the common misconceptions that were identified in this

study. For example, in question 5.3 where students needed to explain why the

passengers in a heavier car were less likely to get injured during a collision; the majority

of students either referred to the physical property of the cars or described what was

happening, thereby activating the misconception that heavier cars exert a greater force.

Thus I found that the main types of misconceptions held by the students in the sample

were misconceptions related to what happens to physical objects during certain events

(genetic misconceptions), and misconceptions related to how certain physical properties

affect what happens to objects or bodies (mechanical misconceptions). Since students

use their misconceptions to construct explanations about their everyday experiences

and observations, it is understandable that students tend to construct mostly genetic

and mechanical explanations. These explanation-types may then reveal misconceptions

about what happens in certain situations and about how observable physical properties

affect certain situations.

To a lesser degree students held misconceptions found in functional (12%) and rational

(5%) explanations. In the erroneous functional explanations students revealed

misconceptions regarding the function of objects, and referred to the function of an

object rather than offering a rational explanation based on Physics principles. In

question 14.3, for example, some students held the misconception that a cut-off switch

is important because it lowers the voltage and saves electricity. In the erroneous

rational explanations that students constructed, students revealed misconceptions

regarding the relationship between various physical quantities. Although students

constructing these types of explanations attempted to apply laws of Physics to explain

the phenomena, they did so incorrectly. These students often only considered two of the

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variables in a Physics equation and neglected the third variable. For example, in

question 5.3 students argued that the heavier car has more momentum because p=mv.

5.2.3.2 Explanation-types reveal the sources of misconceptions

Students themselves are a source of misconceptions. They view the world through the

lenses of their own beliefs (Carr et al., 1994; Strike, 1983) and construct explanations

as to how the world around them works (Smith, diSessa & Roschelle, 1993), based on

these beliefs. Hence their inclination to either formulate genetic explanations (41% of

misconceptions found in this study), by describing what happens, or mechanical

explanations (37% of misconceptions found in this study) by providing evidence in terms

of an object’s physical features.

The interaction between students, their peers, their family, their teachers, their

textbooks and even scientists’ theories are another source of misconceptions. Teachers

and textbook writers, in trying to simplify matters, construct explanations which are

misinterpreted by students. For example, when students are taught that momentum is

conserved during collisions and explosions in closed systems, students may construct

the misconception that momentum is not conserved in open systems and that it is

somehow converted to something else or lost, like energy. Real world problems rarely

adhere to the conditions under which scientific theory exists; thus scientific theories and

their conditions of application can be a source of misconceptions. The classroom

environment and other motivational factors also influence the conceptual development

of a student. If a student is not motivated to learn it will affect the way that new

information is interpreted and whether or not it will be connected to existing knowledge

frameworks.

Language is another source of misconceptions. The manner in which students interpret

new information and link it to their preconceptions is influenced by how well they

understand the language used by their teachers, peers or textbooks. Many of the

students who wrote this exam were writing it in their second language, which explains

why their command of English is so poor and why they hold many misconceptions.

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Misconceptions revealed in this study, such as “energy, voltage, electricity, current, and

power is the same thing” originate because students to not understand scientific

language. The incongruence’s between scientific language and everyday language is

another source of misconceptions. Often words do not have the same meaning in

Physical Sciences as in everyday language, this causes a misconception such as that

mass is the same as weight or that energy is lost.

Assessment causes misconceptions by over-emphasising exemplar-type problems and

selected response questions, by decontextualising knowledge and by using an

unfamiliar context or even by using everyday contexts. The influence of assessment on

misconceptions extends even further, as the stress caused by assessment hinders the

development of students’ conceptual understanding. In this study I found that the 2008

NSC Physics exam consists of 21% explanation-type questions and 79% non-

explanation-type questions, thereby illustrating the over-emphasis of exemplar-type

calculation questions which encourages rote learning.

The introduction of contextual application questions has also affected the occurrence of

misconceptions, because the everyday-life situations act as contextual cues to

misconceptions. Also, the introduction of restrictions in the application of Physical

Sciences theory impacts the formation of student misconceptions. For example, when

students are told that conservation of momentum only applies in closed systems, they

develop the misconception that Physical Sciences only applies to the context sketched

in Physical Sciences examples and that momentum is not conserved in open systems.

5.3. IMPLICATIONS FOR TEACHERS AND OTHER ROLE-PLAYERS IN

EDUCATION

These findings have important implications for teaching and learning. Research shows

there is often little or no change in conceptual understanding before and after formal

instruction and that students are unable to apply the concepts that they have studied to

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certain tasks (Walsh, Howard & Bowe, 2007). A possible scenario which contributes to

this status is that at school there is a strong focus on the solving of problems by the

direct application of previously learnt algorithms. Such problems often appear in

textbooks and it would be more apt to refer to these “problems” as exercises since they

provide practice to the students in applying an algorithm, and they merely serve to

reinforce what has been learned in class. Many studies have shown that although

students are able to solve these quantitative problems by simply plugging values into

formulae and obtaining a correct answer, they lack a fundamental understanding of the

concepts to solve more complex problems (e.g., Ding, Reay, Lee & Bao, 2009; Hunt &

Minstrell, 1994; Leonard, Dufrense & Mestre, 1996; Tuminaro & Redish 2005). The

predominance of this plug-and-chug approach has meant that students are given scant

opportunity to engage qualitatively with concepts in Physics. This was abundantly

evident from the analysis of student responses to the explanation-type questions in this

study where it was clear that students had little or no understanding of the Physics

concepts. Reasons for this scenario include the heavy emphasis in high stakes

examinations being placed on tasks which lend themselves to a plug-and-chug

approach. This was the case in the Physics examination which formed the focus of this

study where the majority of questions could be solved in this way. Therefore, I

recommend that examiners work towards developing a better balance between the type

of questions that target the conceptual knowledge of students and predictable

quantitative questions.

In light of this finding I recommend that a more deliberate and concerted effort be made

to engage students with their conceptual understanding of scientific phenomena.

According to Walsh, Howard and Bowe (2007), a large body of research in Physics

education has reaffirmed research from cognitive psychology that for students to

develop their conceptual understanding in Physics, instruction must first start with their

prior conceptions (e.g., Redish, 2003; Redish, Saul & Steinberg, 1998; Roth, 1990). As

pointed out earlier, these prior conceptions which often are misconceptions, are

resistant to change and traditional approaches such as those described above make

little or no difference to the conceptual beliefs of students. An effective teaching

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approach must allow for students to restructure their own understanding by first seeing

where, when and why their conceptions fail. Only after this can students start to build up

a new and correct understanding. Studies that have explored qualitative discussions in

the teaching of Physics have concluded that this is an effective means of reducing the

number of misconceptions (e.g., Eryilmaz, 2002; McConney, 1992; Nussbaum &

Novick, 1982). Such an approach would entail using conceptual questions to help

students make explicit their conceptions of a phenomenon, presenting discrepant

events to create conflict between the exposed preconception and the observed

phenomenon the student cannot explain, and making students aware of this conflict.

In addition to the use of qualitative discussions the use of writing activities is

recommended as a complimentary approach to developing conceptual understanding

and dealing with personal misconceptions (Carlsen, 2007; Hein, 1999; Mintzes et al.,

2001; Treagust et al., 2001). Emig, cited by Grimberg and Hand (2009, p.504), argues

that “because writing is often our representation of the world made visible, embodying

process and product, writing is more readily a form and source of learning than talking.”

Furthermore, as indicated in this study, many students do not have the linguistic ability

to cope with writing exams, hence the use of writing activities in a supportive

environment such as the classroom has “an added benefit for all of the students,

whether English is their first language or not: that is their communication skills are

enhanced” (Hein,1999, p.140). Teachers can use writing activities such as folder

activities (Hein, 1999) or Science Writing Heuristic (SWH) activities (Akkus et al., 2007;

Grimberg & Hand, 2009; Hand, 2004) to develop the conceptual understanding of their

students. Hein (1999) describes her folder activities as a collection of writing activities

which require students to explain a problem or a concept in their own words and with

enough detail so that someone who did not attend the class would be able to

understand their explanation. Akkus et al., (2007, p.1748) describe the SWH as a

different option to the conventional laboratory report; the SWH requires students to

complete sections on: “questioning, knowledge claims, evidence, description of data

and observations, and methods, and to reflect on changes to their own thinking.” Hence,

authors of Physical Sciences textbooks should design and include more explanation-

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type tasks such as those which formed the focus of this study so that students are

forced to engage qualitatively with Physical Sciences concepts.

Two other teaching approaches that have been highlighted in this study are the use of

concept maps and practical investigations. Teachers can use concept mapping as a

strategy to develop student conceptions by firstly guiding students through the process

of constructing a concept map and then by giving them the opportunity to construct their

own concept maps at the start of a new content area. Concept maps can be used by

teachers to identify student’ preconceptions and further inform the teaching process

(Trowbridge & Wandersee, 1998). Since concept maps are intended to represent the

“cognitive networks that have been constructed by students in the process of learning”

(Klassen, 2006, p.834) they can be modified by the students throughout the learning

process in order to allow for both reflection on, and the extension of, the student’s

understanding (Mintzes et al., 1998). In this study I found that many students held the

misconception that energy, voltage, electricity, current, and power are one and the

same thing. The use of concept mapping of these basic concepts will be particularly

useful in diagnosing this misconception and in developing the students’ conceptual

framework of these concepts. Since students use their preconceptions to construct

explanations for their experiences and observations, it is important for teachers to

provide them with new experiences such as practical experiments which are anomalous

when compared to their preconceptions. In this study I found that many students did not

know the difference between a split-ring commutator and slip rings. The use of practical

investigations will assist students in addressing such misconceptions. Research also

indicates that learning outcomes of practical investigations can be improved by

introducing techniques such as “open-ended investigations that devolve as many

decisions as possible to the students” (Moore & Harrison, 2004, p.1). Predict-Observe-

Explain (POE) is another technique where students are shown an authentic situation,

are then asked to give their prediction about how a specific change to the situation will

affect the situation, then get to observe the changes, write down their observations, and

lastly attempt to reconcile their predictions and observations (Gunstone & Mitchell,

1998). The in-service training of teachers regarding the identification of misconceptions

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and the remediation of misconceptions, through the use of alternative teaching

approaches such as those mentioned in this section, is a recommendation of this study.

Research has shown that alternative teaching approaches designed to develop

conceptual understanding, such as those discussed in the previous paragraphs, are

seldom employed due to time constraints (Ruiz-Primo, Tsai & Schneider, 2010). Over

laden syllabi do not allow adequate time for conceptual reflection (Canpolat, 2006;

Zuzovsky & Tamir, 1999). Metz (in Beeth & Hewson, 1999, p.753) argues that the

“strategic selection of a small number of domains for children’s science, together with

the scaffolding of scientific inquiry in interaction with the scaffolding of relatively deep

understanding within these spheres, more effectively can support children’s construction

and refinement of scientific knowledge.” The issue of having fewer topics in the

curriculum will need to be seriously looked at by South African curriculum planners as

we currently have a curriculum which is considered by most teachers to be overloaded

(Kriek & Basson, 2008).

5.4. CRITIQUE OF THE STUDY

This study is a content analysis, which seeks to make meaning out of students’

responses to the explanation-type questions found in the 2008 NSC Physics

examination. The strength of the study is that I collected both numerical and textual data

from a relatively large sample of 921 student examination answer booklets. The

analysis of the student examination responses was supplemented with local school-

based tests and interviews in order to improve the validity of the data. However, despite

these strengths, the study has the following limitations:

1. A large percentage (52%) of the student responses were classified as

inconclusive in terms of misconceptions. The category of “inconclusive” was not

a part of the original classification, but I was forced to include it after it became

clear to me that many responses that were incorrect lacked sufficient evidence to

be coded a misconception. I do not contend here that students who produced

these responses did not have a misconception inherent to their explanation, but

155

merely that there was a lack of evidence in the explanation for me to infer that a

misconception existed. Many cases which fell into this category suggested poor

readability of the question as student responses were not focussed on what was

demanded in the question. A possible improvement regarding the classification of

inconclusive student responses may be to add an extra category, such as the

category of “non-explanations” as identified by Gilbert et al. (1998a). Perhaps in

future studies a variety of explanation frameworks could be fused to gain an even

greater degree of inclusivity.

2. This study focussed on the Physics content area and identified five common

misconceptions in the mechanics and electricity content areas. The questions in

the examination paper regarding mechanics and electricity yielded more

descriptive answers than those regarding optics. The strength in this focus was

that it allowed for greater depth of analysis. However, the limitation is that it

provided no information regarding optics.

3. The interview sample size of ten students and two teachers drawn from only one

school is too small for the generalisation of results. A larger sample in terms of

schools, students and teachers involved could have given a clearer picture of the

misconceptions held by SA grade 12 Physics students. Also, the questions asked

during the teacher interviews could have focussed more on the teachers’

knowledge of the specific misconceptions held by their students. Also, according

to Henning et al. (2004) the validity of qualitative research studies, such as this

one, can be improved by asking the students and teachers in the interview

sample whether the findings make sense to them

5.5. RECOMMENDATIONS FOR FUTURE STUDIES

Over the past decade there have been numerous studies regarding misconceptions in

Physical Sciences. However, teacher and student awareness of misconceptions

remains lacking and misconceptions seem to persist despite attempts at remediation.

Hence, the domain of student misconceptions requires further investigation. Future

studies need to focus on further identification of specific misconceptions and their

156

sources, especially in fields such as optics, which are new to the SA curriculum. It is

also important to conduct further research using interview data as this allows the

researcher to probe for more in-depth information regarding student understanding, and

allows the student more time to express and reflect on their conceptions. Research on

conceptual change has also received much attention, however, these new teaching

strategies need to be tested and further developed in SA classrooms. This study

commented on the serious language barriers which are a source of many

misconceptions, hence it is vital that future studies investigate teaching strategies to aid

students with language barriers.

5.6. SUMMARY

In this study I set out to identify the types of explanations and misconceptions

constructed by Physics students and the relationship between student explanations and

misconceptions. I have shown that SA grade 12 students perform poorly in explanation-

type questions and construct predominantly genetic and mechanical explanations.

These explanations reveal misconceptions about what happens to objects in certain

situations as well as misconceptions about how physical properties affect what happens

to objects. I have also shown that students co-construct misconceptions during their

interaction with family, peers, teachers and learning material. Other sources of

misconceptions are language barriers, which are particularly prevalent in SA schools,

and a misplaced focus of assessment on quantitative problem-solving. There are other

factors that influence the construction of misconceptions, factors such the learning

environment and motivation of students. There is a need for the implementation of

teaching strategies that focus on greater depth in conceptual understanding, teaching

strategies such as qualitative discussions, writing activities, conceptual mapping and

more effective practical investigations. However, in order to enable the implementation

of such conceptual change strategies the curriculum needs to be narrowed down to

allow for more depth in understanding and assessment needs to include more

qualitative explanation-type conceptual questions.

157

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Appendix A

Ethical Clearance from UJ

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Appendix B

Approval form to conduct research from Department of Education

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Appendix C

Permission letter to conduct research from Department of Education

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Appendix D

Letter of consent to school principal

45 Sable Mansions Mooikloof Ridge Moreleta Park 27th January 2009

To the principal, HOD of Sciences and the grade 12 Science teacher Requesting permission to involve your Science students and Science teacher in a research project. I am currently conducting a study on student misconceptions in the 2008 grade 12 National Senior Certificate Physics examination, as part of my Masters studies. In order to construct a better understanding of these misconceptions it is necessary for students, participating in this study, to answer a worksheet which contains nine explanation-type questions from the 2008 grade 12 National Senior Certificate Physics examination. This worksheet may be completed during any Science lesson, under test conditions, to allow students the opportunity to think about their answers carefully. Thereafter I will mark the worksheets, identify the common misconceptions and then ask about 10 students that hold these misconceptions to participate in an interview of approximately a half an hour each. I would also need to interview the grade 12 Science teacher, as she may have valuable information regarding the misconceptions that her students hold. I would like to conduct this study at your school at the start of the third term. If you agree to allow me to involve your students and science teacher, I will request written permission from the parents and students to participate voluntarily and anonymously. In a letter requesting their participation, I will explain the benefits of participation to the students. Such benefits include the opportunity to practice typical exam questions and receive valuable feedback regarding personal misconceptions that could affect their performance in their final examination. I am also in the process of gaining permission from the Gauteng Department of Education to conduct this research. I hereby request your permission to involve your Science students and Science teacher in this research project. Kind regards Celeste van Niekerk ________________________

Permission granted/not granted

Concerns regarding participation: ___________________________________________________________________________________________________________________________________________________________________________________________________________________________

Signed by: _________________________________________________________________________

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Appendix E

Letter of consent to science teachers

P.O. Box 174 Menlyn 0063 Cell: 082 688 0834

______________________________________________________________________ TO: The Science Teachers FROM: Celeste van Niekerk RE: Request to conduct research DATE: 29 June 2009 ______________________________________________________________________ The purpose of this letter is to request permission to determine your opinion regarding the extent to which student misconceptions are prevalent in your classes, possible sources of misconceptions and the strategies that you are using to address these misconceptions. It would be appreciated if you could participate in a one-to-one interview in my research study. Please note that you are at liberty to withdraw from this study at any time, without penalty or pressure from me, as the researcher, to provide reasons. In this regard, I will undertake to ensure that participating in this study does not disadvantage you. It is also my belief that there are benefits for you. Your input will contribute to making teachers more aware of the types of misconceptions and sources of misconceptions that students struggle within their Physics exams. It will also be a valuable opportunity to reflect on teaching strategies that are useful to address these misconceptions. Please note that all information supplied will be treated with confidentiality and outcomes of the research will be made available on request. Tape recordings/data will be kept under lock and key and will be destroyed after completion of the research study. Your cooperation and time is highly appreciated. Yours in Education _______________________ _________________________ Celeste van Niekerk Dr U Ramnarain Researcher Supervisor ---------------------------------------------------------------------------------------------------------------- CONSENT

I, _________________________________________________ will participate in the study and give consent that the interview may be tape-recorded. __________________________________ _____________________ Signature of participant Date

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Appendix F

Letter of consent to parents/guardians

45 Sable Mansions

Mooikloof Ridge

Moreleta Park

22nd

July 2009

TO: Parents/guardians of the grade 12 Physical Science students

FROM: Mrs Celeste van Niekerk

RE: Request to conduct research

DATE: 22 July 2009

The purpose of this letter is to request your permission to involve your child in my research study. The grade 12 students of 2008 were the first group of students to write a national examination on a curriculum which is underpinned by outcomes-based education. The performance of students in Physical Sciences was poor. Of the 218 156 students that wrote the paper, 98 060 students (45% of the total) achieved below 30%, and only 62 530 (28, 7%) achieved 40% and above (Department of Education, 2008). Poor results in science education have often been ascribed to students’ misconceptions. Therefore, a great deal of support and guidance is needed with regard to the identification and remediation of students’ misconceptions in Physical Science. I will be conducting research on the causes of grade 12 students’ misconceptions in the Physics exam and on remediation strategies; as part of my Masters Degree at the University of Johannesburg. Research in this area will contribute to improved awareness by teachers and students of common misconceptions that need to be remediated in order to improve student results in Physical Science. The students participating in this study will benefit from this study by getting the opportunity to practice typical exam questions and receive valuable feedback regarding personal misconceptions that could affect their performance in their final examination.

To participate in this study your child will need to answer a worksheet which contains nine explanation-type questions from the 2008 grade 12 National Senior Certificate Physics examination. This worksheet will be completed during a Science lesson next week, under test conditions, to allow students the opportunity to think about their answers carefully. Thereafter I will mark the worksheets, identify the common misconceptions and then ask

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about 10 students that hold these misconceptions to participate in an interview of approximately a half an hour each.

Please note that students are at liberty to withdraw from this study at any time, without penalty or pressure to provide reasons to me, as the researcher. In this regard, I will undertake to ensure that participating in this study does not disadvantage the participants. All the information supplied will be treated with confidentiality and outcomes of the research will be made available on request. Data will be kept under lock and key and will be destroyed after completion of the research study.

Should you have any queries or comments regarding this research study, you are welcome to make contact with me at 082 688 0834. Your cooperation is highly appreciated. Yours in Education

CELESTE VAN NIEKERK DR U RAMNARAIN

Researcher Supervisor ----------------------------------------------------------------------------------------------------------------------

CONSENT REPLY SLIP (Please return this slip to your Science teacher by Monday the 27th July) I, ________________________________________________________, the parent/guardian of ________________________________________ give my consent that he/she may participate in the study and that the information may be used confidentially for research purposes.

___________________________ _____________________

Signature of parent/guardian Date

185

Mmmm Science

Research????

Appendix G

Letter of assent to students

Dear student You are kindly requested to complete a Science worksheet during one of your Science lessons next week. The worksheet consists of nine explanation-type questions which were taken from the 2008 grade 12 National Senior Certificate Physics examination. The aim of the worksheet is to identify possible misconceptions that you and ultimately other students may have regarding these typical Science exam questions. The ultimate aim of the research study is to make teachers aware of what misconceptions Science students are struggling with. It will take approximately 30 minutes to complete the worksheet and it should be completed during class under supervised examination conditions. Afterwards I will mark the worksheets and give you feedback about any misconceptions that you may have. The worksheets will not be used by the school for any form of assessment and you are not required to study anything beforehand. I will then identify a few students to conduct an interview with so that I can make sure that I understand your answers and possible misconceptions. I assure you that your identity and your responses to the worksheet will be treated as CONFIDENTIAL at all times and that it will NOT be made available to any unauthorized user. Please note that you are at liberty to withdraw from this study at any time, without penalty or pressure from me, as the researcher, to provide reasons. In this regard, I will undertake to ensure that participating in this study does not disadvantage you. Should you have any queries or comments regarding this research, you are welcome to contact me via your teacher. Your cooperation is highly appreciated. Yours in Education CELESTE VAN NIEKERK Researcher ----------------------------------------------------------------------------------------------------------------------

CONSENT REPLY SLIP (Please return this slip to your Science teacher by Monday the 27th

July) I, ___________________________________________________, the student have read and understand the aims of this research study and agree to participate in the study. ___________________________ _____________________ Signature of student Date

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Appendix H

2008 NSC Physics examination

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Appendix I

Possible answers for the 2008 NSC Physics examination

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Appendix J

Pre-interview test

Grade 12 Physics Worksheet.

Instructions

Read each of the nine questions carefully and then write down your answer as

thoroughly as possible. Take time to write down everything that comes to mind

regarding the answer to the question. None of the questions involve calculations, they

are all questions that require you to explain or describe something.These questions are

not for assessment purposes, they will be used to find out why you think that your

answers could be correct.

Question 1

A circuit is connected as shown below. The resistance of R, which is connected in

parallel with the 10 Ω resistor, is unknown. With switch S closed, the reading on

voltmeter V decreases from 45 V to 43,5 V. The internal resistance of the battery is 0,5

Ω.

How will the reading on voltmeter V change if resistor R burns out? Give a reason for

your answer.

Question 2

A coil is rotated anti-clockwise in a uniform magnetic field. The diagram below shows

the position at the instant the coil lies parallel to the magnetic field.

What type of generator is illustrated in the diagram? Give a reason for your answer.

229

Question 3

An ink-jet printer makes use of the electric field between two oppositely charged parallel

plates to control the position of an ink drop on paper.

In the diagram below, the generator (G) of the printer shoots out ink drops that are

charged in the charging unit C. The input signal from a computer controls the charge

given to each ink drop. P is a negatively charged ink drop.

Is plate B negatively or positively charged? Give a reason for your answer.

Question 4

A helium-neon laser emits red light that passes through a single slit. A diffraction pattern

is observed on a screen some distance away from the slit.

4.1. Briefly describe the pattern that will be observed on the screen.

The single slit is replaced with a double slit.

4.2 Name ONE similarity and ONE difference in the pattern observed when the


4.3. Will this pattern be observed if the laser is replaced with a light bulb? Give a


Question 5

It is common practice to connect many appliances to a multi-plug. Modern types of

multi-plugs have a cut-off switch built in. Using principles in Physics, explain clearly why

this cut-off switch is important.

230

Question 6

Learners investigate the conducting ability of two metal wires P and Q, made of different

materials. They connect ONE wire at a time in a circuit as shown below.

The potential difference across each wire is increased in equal increments, and the

resulting current through these wires is measured. Using the measurements, the

learners obtained the following sketch graphs for each of the wires.

Which one (P or Q) is the better conductor? Explain your answer.

Question 7

A fully automatic camera has a built-in light meter. When light enters the light

meter, it strikes a metal object that releases electrons and creates a current.

The intensity of the incident radiation on the metal plate is increased whilst

maintaining a constant wavelength of 200nm. State and explain what effect

this change has on the following:

5.1. The energy of the emitted photo-electrons

5.2. The number of emitted photo-electrons

231

Question 8

The diagram below represents how water is funnelled into a pipe and directed to a

turbine at a hydro-electric power plant. The force of the falling water rotates the turbine.

Each second, 200 m of water is funnelled down a vertical shaft to the turbine below.

The vertical height through which the water falls upon reaching the turbine is 150m.

NOTE: One m³ of water has a mass of 1000 kg.

Assume that a generator converts 85% of the maximum kinetic energy gained by the

water, as it falls, into hydro-electricity. Explain what happens to the 15% of the kinetic

energy that is NOT converted into electrical energy.

Question 9

The most common reasons for rear-end collisions are too short a following distance,

speeding and failing brakes. The sketch below represents one such collision. Car A of

mass 1000kg, is stationary at a traffic light, and is hit from behind by Car B of mass

1200kg, travelling at 18m. . Immediately after the collision Car A moves forward at

12m. .

9.1. Modern cars are designed to crumple partially on impact. Explain why it may

NOT be valid to assume that linear momentum is conserved in accidents such as

the one described above.

9.2. A traffic officer appears at the scene of the accident and mentions the dangers of

a head-on collision. He mentions that for cars involved in a head-on collision, the

risk of injury for passengers in a heavier car would be less than for passengers in

a light car.

Use principles of Physics to explain why the statement made by the traffic officer

is correct.

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Appendix K

Extended memorandum for pre-interview test

Grade 12 Physics Worksheet Memorandum.

Instructions

Read each of the nine questions carefully and then write down your answer as

thoroughly as possible. Take time to write down everything that comes to mind

regarding the answer to the question. None of the questions involve calculations, they

are all questions that require you to explain or describe something. These questions are

not for assessment purposes, they will be used to find out why you think that your

answers could be correct.

Question 1

A circuit is connected as shown below. The resistance of R,

which is connected in parallel with the 10 Ω resistor, is

unknown. With switch S closed, the reading on voltmeter V

decreases from 45 V to 43, 5 V. The internal resistance of the

battery is 0, 5 Ω.

How will the reading on voltmeter V change if resistor R burns out? Give a reason for

your answer.

Question 2

A coil is rotated anti-clockwise in a uniform magnetic field. The diagram below shows

the position at the instant the coil lies parallel to the magnetic field.

What type of generator is illustrated in the diagram? Give a


233

Question 3

An ink-jet printer makes use of the electric field between two oppositely charged parallel

plates to control the position of an ink drop on paper.

In the diagram below, the generator (G) of the printer shoots out ink drops that are

charged in the charging unit C. The input signal from a computer controls the charge

given to each ink drop. P is a negatively charged ink drop.

Is plate B negatively or positively charged? Give a reason for your answer.

Question 4

A helium-neon laser emits red light that passes through a single slit. A diffraction pattern

is observed on a screen some distance away from the slit.

4.1. Briefly describe the pattern that will be observed on the screen.

The single slit is replaced with a double slit.

4.2 Name ONE similarity and ONE difference in the pattern observed when the


234

4.3. Will this pattern be observed if the laser is replaced with a light bulb? Give a


235

Question 5

It is common practice to connect many appliances to a multi-plug. Modern types of

multi-plugs have a cut-off switch built in. Using principles in Physics, explain clearly why

this cut-off switch is

important.

236

Question 6

Learners investigate the conducting ability of two

metal wires P and Q, made of different materials.

They connect ONE wire at a time in a circuit as

shown below.

The potential difference across each wire is

increased in equal increments, and the resulting

current through these wires is measured. Using the

measurements, the learners obtained the following

sketch graphs for each of the wires.

Which one (P or Q) is the better conductor? Explain

your answer.

237

Question 7

A fully automatic camera has a built-in light meter. When light enters the light


The intensity of the incident radiation on the metal plate is increased whilst

maintaining a constant wavelength of 200nm. State and explain what effect

this change has on the following:

5.1. The energy of the emitted photo-electrons

5.2. The number of emitted photo-electrons

Question 8

The diagram below represents how water is funnelled into a pipe and directed to a

turbine at a hydro-electric power plant. The force of the falling water rotates the turbine.

Each second, 200 m of water is

funnelled down a vertical shaft to the

turbine below. The vertical height

through which the water falls upon

reaching the turbine is 150m.

NOTE: One m³ of water has a mass of

1000 kg.

Assume that a generator converts 85% of the maximum kinetic energy gained by the

water, as it falls, into hydro-electricity. Explain what happens to the 15% of the kinetic

energy that is NOT converted into electrical energy.

238

Question 9

The most common reasons for rear-end collisions are too short a following distance,

speeding and failing brakes. The sketch below represents one such collision. Car A of

mass 1000kg, is stationary at a traffic light, and is hit from behind by Car B of mass

1200kg, travelling at 18m. . Immediately after the collision Car A moves forward at

12m. .

9.2. Modern cars are designed to

crumple partially on impact. Explain why it may NOT be valid to assume that linear

momentum is conserved in accidents such as the one described above.

9.2. A traffic officer appears at the scene of the accident and mentions the dangers of

a head-on collision. He mentions that for cars involved in a head-on collision, the

risk of injury for passengers in a heavier car would be less than for passengers in

a light car.

Use principles of Physics to explain why the statement made by the traffic officer

is correct.

239

Appendix L

Exemplars of classification-grid data

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241

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Appendix M

Questionnaire schedule for interviews

Teachers:

1. Tell me, in your experience with the Science students in your class, how common

are student’ misconceptions?

2. How do you think students develop misconceptions?

3. From your point of view, what would you say are the main sources of student’

misconceptions?

4. How would you define a misconception?

5. What strategies do you use or have you tried, which may remedy student’

misconceptions?

6. Have you received any training or attended any course or meeting where

student’ misconceptions in Science or strategies for remedying them has been

discussed? Tell me about that.

7. Have you come across any articles on students misconceptions while reading

about Science? Tell me about that.

8. Have you come across any misconceptions in Science textbooks? Tell me about

those.

9. What are the most common misconceptions that you have come across in your

grade 12 students Physics papers?

10. In your opinion would practical work and experiments have any effect on student

misconceptions? Tell me about that.

11. Do you think that language would have any effect on student misconceptions?

Tell me about that.

12. Do you think the language of Science terminology would have any effect on

student misconceptions? Tell me about that.

244

Students:

1. When a heavy vehicle collides into a lighter car the passengers in the lighter car

are likely to be injured more seriously. Tell me from a scientific point of view why

this happens.

Why do you think that cars with a greater mass exert a greater force on lighter

cars during a collision?

Where do you think you got the idea that heavier cars exert a greater force on

lighter cars during a collision?

Explain to me what impulse is.

Explain the difference between weight and mass.

Newton’s third law states that for every force there is an equal but opposite force.

How would you apply this law to the heavy and light car that collided head- on?

During a head-on collision both the lighter and the heavier car experiences a

deceleration. Do you think the cars experience the same acceleration? Explain

why/why not.

Where would you say you got most of these ideas on momentum? Where else?

In certain collisions linear momentum isn’t conserved. When would you say does

that happen?

Explain why you think momentum isn’t conserved when that happens.

What would you say is the difference between an elastic collision and an inelastic

collision?

2. At a hydro-electric power plant the generator converts about 85% of the water’s

kinetic energy into hydro-electric energy. What happens to the other 15% of the

kinetic energy?

Explain what you mean when you say the energy is lost. Where would you say

you got the idea that the energy is lost? Does this idea of lost energy match up

with the law of conservation of energy? Why/ Why not?

3. What happens to the voltmeter reading if resistor R burns out?

245

Tell me more about why you think the voltmeter reading will increase if there is

less resistance in the circuit?

What potential difference would you say the voltmeter measures when it is

connected in the position shown in the diagram?

What does a voltmeter actually measure? What are volts?

Tell me more about why you think the circuit’s resistance will be less when

resistor R burns out?

4. What type of generator is illustrated in the diagram?

Tell me more about the difference between an ac and a dc generator.

Is there a difference between a split-ring and a slip-ring? What is the difference?

Where do you find a split-ring and a slip-ring?

5. Modern types of multi-plugs have a cut-off switch built in. Why are they so

important?

What do you think could cause the power to get too intense? What exactly is

power?

Explain to me in more detail why the components get hot.

Explain how the components take more volts.

Tell me, what are volts?

246

When you connect components into a multi-plug, would you say they are

connected in series or parallel? Explain your answer.

If the components are connected in parallel in a multi-plug, then what happens to

the resistance as you add resistors in parallel?

What happens to the current in the circuit if the resistance decreases?

6. What is the charge on plate B if the ink droplet in the diagram is negatively

charged? Explain your answer.

Tell me more about how this works.

7. When a laser emits red light that passes through a single slit, a diffraction pattern

can be seen on a screen some distance away from the slit. What does the

diffraction pattern look like?

Tell me more about what it will look like. What colour?

Have you seen a diffraction pattern? Where?

If the single slit is replaced with a double slit, what similarity will you notice

between the patterns formed?

If the single slit is replaced with a double slit, what difference will you notice

between the patterns formed?

Have you seen a double split interference pattern? Where?

What will you observe if the laser is replaced with a light bulb?

Are there any other differences you can think of between the laser and a light

bulb?

247

8. The conducting ability of two metal wires P and

Q was tested, by measuring the current running

through the wires and the potential difference

across the wires. Results as in this diagram

were obtained:

Which conductor is a better conductor?

Tell me more about why having the highest potential difference would make P

the better conductor.

How would P get a higher potential difference across it?

What would you say have conductivity and current got to do with one another?

Explain to me what the gradient of this graph represents.

9. A fully automatic camera has a built-in light meter. When light enters the light


What happens to the energy of the emitted photo-electrons if the intensity of the

incident radiation is increased, whilst maintaining a constant wavelength?

Tell me why you think the energy of the photo-electrons will increase if the

incident radiation increases?

What do you think it means when the wavelength of the radiation stays constant?

What do you think increases when you increase the incident radiation without

changing the wavelength?

What would you say happens to the number of photo-electrons emitted when the

incident radiation increases?

Have you seen a light meter or photo-electric cell? Where? Where would you say

did you get most of your ideas about the photo-electric effect?

248

Appendix N

Transcripts of student interviews

N1: Interview with the first student on 12/08/2009 at 11h00-11h15

Researcher: In your worksheet over here, you wrote that: “wire P will be a better

conductor, because it provides the highest level of potential difference.”

Can you tell me more about why you think that because wire P has a

higher potential difference that will make it a better conductor?

Student 1: I have no idea, honestly mam I was guessing on that because I do very

badly in what's its name.

Researcher: Electricity?

Student 1: Yes mam, (Pause).

Researcher: OK, but why do you think you guessed that? Why would that be your

guess? When wire P has a bigger potential difference?

Student 1: Ummm, I suppose…

Researcher: Let me show you the circuit again. The circuit looks like this, (showed

learner the circuit on the worksheet) so there’s wire P.

Student 1: Mmm

Researcher: And now you said that it has a higher potential difference, there is the

voltmeter and the voltmeter is giving you that reading. And so you said

that you think that it’s got something to do with potential difference. The

fact that it has a higher potential difference makes it a better conductor.

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Why do you think you guessed that, do you think there is a connection

between potential difference and being a good conductor?

Student 1: Pause. I have no idea. I think I looked at it and I can’t remember but I was

thinking of... what was I thinking?, Pause, umm what was I thinking now?,

Pause, I figured that if it has a high potential difference then it will have, I

really can’t remember mam.

Researcher: Can you think of the connection between V and A.

Student 1: No.

Researcher: Potential difference and current? Do you know of some relationship

between those?

Student 1: I don’t know…

Researcher: Or an equation between those two?

Student 1: I=V, no, there is a V and a I somewhere, pause isn’t it I=V/R, no, R=, but

then there was no R here so I just figured…

Researcher: So you knew there was some relation there, ok in that relationship there is

R, and here there is no R?

Student 1: Mm.

Researcher: What is the wire?

Student 1: Which wire mam? This wire?

250

Researcher: Ja, that wire. Could that be the R?

Student 1: I suppose because they always draw the resistor like that.

Researcher: Ok, so it could be the resistor. Ok so if it was the resistor, then this V and

R could have something to do with the resistor (finding it very difficult not

to explain it to her, I think I already am). What do you think resistance has

got to do with conductivity? Because here they wanted to investigate

which metal is a better conductor. What has conductivity got to do with

resistance? Because you know that there is a connection here between V

and I and R?

Student 1: MM

Researcher: But they are asking about conductivity, what has conductivity got to do

with resistance? Is there any connection between conductivity and

resistance?

Student 1: Pause, I don’t think so.

Researcher: You don’t think so?

Student 1: Well, conductivity isn’t it like related to electricity, but then this one resists

it, doesn’t it like resist.

Researcher: What is resistance?

Student 1: Resistance? I think like it decreases I wonder a current that flows or

something.

Researcher: So what would you say then is the relationship between conductivity and

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resistance?

Student 1: That they are directly proportional, no no, I wonder, no, ugh, I suppose

that the higher the resistance the less the conductivity (very hesitant).

Researcher: Ok, so in other words you know that if the resistance is high the

conductivity is low.... ok let’s see what else there is, if you now had to

have a look at this graph, what do you think the gradient of this graph

represents?

Student 1: Could it be resistance? Pause. This is I right and this is V?

Researcher: How do you work out the gradient of a graph?

Student 1: Gradient, a change in y over change in x.

Researcher: Ok so it would be?

Student 1: Um, it would be this over that, (pause).

Researcher: Ok and what would that then be?

Student 1: R? No, it can’t be resistance; I think it’s got to do with resistance I’m not

sure.

Researcher: So it’s got to do with resistance? So in a way it is telling you conductivity?

It’s got something to do with that.

Student 1: Why didn’t I think of that?

Researcher: Did you think of the gradient when you answered the question?

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Student 1: Not at all, honestly speaking.

Researcher: You just saw that there were the same values there but you didn’t think of

the gradient?

Student 1: I didn’t and I umm with electricity we haven’t really touched it like the last

time we actually did something extensive on electricity was like in grade 9.

Researcher: Ok, in grade 11, last year?

Student 1: Last year, it was um what is it um self study, I think, because we didn’t

have enough time or something.

Researcher: In grade 11 and you haven’t done it in grade 12?

Student 1: No we haven’t, no yes did we do it?

Researcher: Did you do electricity in grade 12?

Student 1: Yes I think so mam.

Researcher: So you think so, but you don’t remember that much?

Student 1: No.

Researcher: Ok, let’s look at another question. Pause. Ok, let’s look at this one.

Student 1: Ooo, that’s a bad one.

Researcher: The question was: What type of generator is this? And you wrote that:

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“this generator is a split-ring generator.” Why do you think that this is a

split-ring generator?

Student 1: I guessed that maybe, I didn’t know the split ring is in it but it can like turn

or something, I don’t know, I can’t remember. But then, jaaa but then….

Researcher: Tell me about the split-ring.

Student 1: That was the only thing that I actually remembered about generators, oh

and ac conductor, ok, ac conductors or something.

Researcher: Do you think that this is an ac or a dc generator, because those are the

two types of generators that you get? So do you think that this is an ac

generator or a dc generator?

Student 1: I think that it is an ac.

Researcher: Ok, so you think it is an ac generator? What is the difference between an

ac generator and a dc generator?

Student 1: AC is alternate current, changing direct current.

Researcher: And physical differences? How would it do that?

Student 1: Umm. Isn’t it that if you can with this umm split ring I think, if you turn it or

something I don’t know it turns or somehow, something about the

magnetic, I really can’t remember.

Researcher: Something about the magnetic?

Student 1: Magnetic field. I can’t remember.

254

Researcher: You spoke about a split-ring, and you also get a slip-ring, do you know the

difference between slip-rings and split-rings?

Student 1: No mam.

Researcher: Ok, so you wouldn’t be able to tell me where you find a split-ring and

where you find a slip-ring?

Student 1: I would, had I actually studied, but I didn’t.

Researcher: Ok, so you haven’t done this type of question for a while?

Student 1: Since, wow, last term.

Researcher: Ok, umm, let’s look at this other question of yours, this question I think

may be more familiar, I think you did it this year. Ok. This is the one about

the collisions with the two cars. The two cars bumping into one another.

Ok, so the question said: “In certain collisions, momentum, linear

momentum, isn’t conserved”, and then the question asks: “when isn’t

momentum conserved”… and you wrote that: “momentum will not be

conserved in this type of collision because the kinetic energy before the

collision is not going to stay the same as afterwards." Explain why you

think momentum isn’t conserved, when this happens.

Student 1: Because, as some of the energy is lost through sound and when and ja

sound, heat.

Researcher: Ok, so energy is lost in sound and so on, so tell me why if energy isn’t

conserved, why do you think momentum isn’t conserved?

255

Student 1: Umm, because there is an external ja it’s not a closed system because

there are external force acting on it (very hesitant). No, no, no I am lying,

oh.

Researcher: You are not actually, say that again.

Student 1: I said something about an external force.

Researcher: What external forces do you think could be acting on those cars?

Student 1: Ah, I wonder is friction an external force? Pause. So there is an external

force? Pause

Researcher: Nod. So the external forces act, that’s why the momentum isn’t conserved.

What have the external forces got to do with energy though?

Student 1: Long Pause. Because isn’t that F=ma, so no no, umm, pause, you said

why is force, what was the question again?

Researcher: What has the force, the fact that there are external forces, got to do with

the energy lost, why is the energy lost when there are external forces?

Student 1: Um, long pause. I don’t know. Pause. This force will cause these things to

move right? And no work don’t know, no, ugh I really …

Researcher: Ok, um just one other thing I wanted to ask, you said that energy is lost

during the collision, because it is changed into heat and sound. Why do

you say energy is lost if it has changed into heat and sound?

Student 1: Yes it is transferred, sorry.

256

Researcher: Transferred? To what?

Student 1: Ja, energy can never be lost only transferred into other forms.

Researcher: Ok so you know energy can never be lost, where did you get that idea

from?

Student 1: We learnt it like.

Researcher: So there is a law?

Student 1: Yes.

Researcher: A Science law? Do you agree with that law? Does your everyday

experience match what you have seen in collisions and that the law that

says energy cannot be lost. Do you believe it; do you think that it is true?

Student 1: That energy cannot be lost?

Researcher: Ahaham.

Student 1: I suppose (hesitant) I never really think about it, I’m going to have to think

about.

Researcher: So why do you say it’s lost if you that the Science law says that energy

isn’t lost, you say that it is so easy to talk about energy lost. Why is it so

easy?

Student 1: Cause we don’t see it. We can’t see…

Researcher: You can’t see the heat? Or where it has gone really?

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Student 1: Yes mam.

Researcher: So that’s why, it’s just a way of talking, that it’s lost, ok. Um there was one

other thing that I was thinking of while you where answering there. Um

when you write your Physics exam, um, when was your last Physics exam

that you wrote? Did you write one in March?

Student 1: I also wrote one in …

Researcher: June?

Student 1: Yes, mam.

Researcher: Do you struggle with the time? Did you finish in time?

Student 1: No.

Researcher: You didn’t finish? (Learner nods) So time was an issue?

Student 1: Yes mam.

Researcher: Because a lot of what you said was correct and you didn’t write it in your

paper. If you had written what you said to me now you would have got lots

more marks. In other words all the answers that were looking for, you

actually know them, but when I asked you to tell me more, explain to me

more then you suddenly said them. Like for example the closed system

that would have been a mark, um I can’t remember now but there were a

few things. Keywords that you said if you had written them you would have

got the marks, so you lost quite a lot of the marks and you actually knew

the stuff but you didn’t write it, do you think it has got to do with the time?

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Student 1: I have a problem, I tend to doubt myself. Like I want to say something and

I try to write it exactly like in the book and if I forget I get blank and then

just move onto the next question, and think I will come back to it.

Researcher: Ok, I think that’s all. When a heavy car collides into a lighter car the

passengers are more seriously injured and you wrote: “the heavier car will

exert a much higher force than the lighter car”, why do you think so, why

do you think that the heavier car will exert a much higher force on the

lighter car?

Student 1: Because it’s mass is greater.

Researcher: Ok and why if its mass is greater will it exert more force?

Student 1: Because the momentum is um directly proportional to the mass and so if

the mass is greater, obviously the momentum is going to be higher, and

isn’t it that F is equal to momentum, so if the momentum is higher than the

force, I don’t know if like it’s there so the force is going to be greater, isn’t

it that the amount of force that it exerts on the small car isn’t it that the

same amount exerts back on the car or something.

Researcher: Ok so now you are saying that it is equal?

Student 1: No no, just that mm ugh, all I know is that the big car is going to hurt the,

it’s going to exert a much greater force than the light car.

Researcher: Where do you think you got the idea that it’s going to exert a bigger force?

Student 1: Umm, because pause, because of the fact that momentum equals mass

times velocity.

259

Researcher: Ok, but if it’s got more mass does that mean it’s got more velocity?

Student 1: Noo, Oooh yeah.

Researcher: Would you say it is from an experience point of view? or from science

lessons?

Student 1: I suppose, I remember mam said something about it.

Researcher: You also wrote that the fact that the stationary car moved also indicates a

greater force by the heavier car, do you think that it is always like that, that

the object that moves is experiencing a bigger force?

Student 1: Yes, cause, I think so, because if like the um the force was the same then

it wouldn’t have moved at all like if you try and push a wall your force is

not big enough so it is not going to move at all.

Researcher: Ok, and what would you say would Newton’s third law work here because

he said that for every force there is an equal opposite force, so when the

two cars hit one another then the force is equal. Does that apply in a

head-on-collision?

Student 1: I think it does apply, I think so.

Researcher: If it applies how come the little car gets hurt more?

Student 1: Stronger materials, I don’t know. (Bell rings)

Researcher: Thank You.

260

Student 1: The crumple zones I suppose.

Researcher: Ok. (The researcher switches off the tape-recorder).

N2: Interview with the second student on 12/08/2009 at 14h15-14h30

Researcher: There we are, (researcher open the learners’ answers to the worksheet)

so how I chose questions, it doesn’t mean that you got the question right

or wrong if I chose the question, it just means that you expressed yourself

and I sort of, it sort of gives me a good understanding of what you are

thinking, but I want to know more. And then also maybe no one else

answered that question so I want all the questions covered. All these

questions come from last years’ Physics paper, ok. So the question that I

want to ask you first is about light. The question says that: “when a laser

emits light through a single slit, then you get a diffraction pattern, and it

can be seen on a screen some distance away from the slit. In your answer

you wrote: “The diffraction pattern consists of many lights, produced on

the medium, when using double slits, one light using the single slit.”

Student 2: Ok.

Researcher: Have you seen a diffraction pattern?

Student 2: Ja, we made a, a small science experiment.

Researcher: Please talk a little louder.

Student 2: We made a small Science experiment, in class and I kind of like remember

a few stuff from xx.

Researcher: When did you do that experiment?

261

Student 2: Um I don’t quite remember, I think it was in March.

Researcher: This year?

Student 2: Ja.

Researcher: Can you tell me more about what it looked like, you said it consists of

many lights, what do those light look like?

Student 2: Ok we used a red laser light, right, so uh, we took paper as the medium

and we put it against the wall and then uh there was a double slit

apparatus and then we light the light through the double slit then it

diffracted, like into I think four lights, four different lights.

Researcher: What colour?

Student 2: It was red.

Researcher: And all the same, all, all the different lights did the whole pattern look the

same?

Student 2: Mm (Laugh)

Researcher: Let’s say I had never seen it, what, you are saying it was a red light, what

did it look like, was it just one blur of red light, or what did it look like?

Student 2: It wasn’t, it was spots.

Researcher: Spots?

262

Student 2: Ja.

Researcher: Ok.

Student 2: It wasn’t a, a, um like a spectrum, like you know, separating all the

colours, it was just …

Researcher: Red spots?

Student 2: Ja.

Researcher: Ok.

Student 2: Showing diffraction.

Researcher: Ok, if the single slit is replaced with a double slit then you get a different

pattern. Ok, um what is the difference between the pattern that you get

when you use a single slit and when you use a double slit? What’s the

difference? Can you remember? Did you do both, the single slit and the

double slit?

Student 2: No, we only did the one slit.

Researcher: Only one slit?

Student 2: Aahah.

Researcher: So you haven’t seen the double slit?

Student 2: No I mean, aah, we did the double slit, but not the single slit.

263

Researcher: So you are not sure, have you seen it in a book or something, the

difference?

Student 2: (Pause) Oh well we, I’ve seen with the water, the double slit with the water

and the single slit with the water, but not with a laser light.

Researcher: Umm, ok then there was another question, the B part of the question, it

said that: “if you replaced the laser with a light bulb …

Student 2: Ok.

Researcher: -and you let the light go through a single slit,

Student 2: Aaha mm.

Researcher: -would you be able to see a diffraction pattern on the paper?

Student 2: I said I don’t think so because it is not strong enough.

Researcher: Ok you said it is not concentrated like a laser. What do you mean by

concentrated?

Student 2: Like a um, how can I explain it, like the strength of the light, you know a

laser you can show a laser and you can see it on the other side of the

room and a light bulb it’s just, aah, you can just light it in a room, one

room, and you can’t see it on the next wall.

Researcher: Ok, and are there any other differences between laser light and a light

bulb, other than that strength that you can think of?

Student 2: Oh, well a laser light just shines on one spot and a light, a light bulb can

264

shine like the whole room, and lighten.

Researcher: Ok. Let us see what other questions you answered. (Pause). The one

about the collisions, with the cars colliding into one another. The question

said: “in certain collisions linear momentum isn’t conserved.” And the

question was: “When is linear momentum not conserved? And you wrote:

“the momentum will not be conserved because the collision may be

inelastic."

Student 2: Aahahm.

Researcher: Why do you think momentum isn’t conserved when a collision is inelastic?

Student 2: Um the difference between the kinetics I think. (Laugh)

Researcher: What’s the difference? (Smile)

Student 2: Mmm?

Researcher: What’s the difference between kinetics?

Student 2: The kinetics, like a, that the kinetic energy, that the a..., the difference in

the mass of the object and ... you know, the velocities and all that, so, so

maybe can’t be the same, can’t you know....

Researcher: What is the difference between an elastic and an inelastic collision?

Student 2: Umm, (you know I can’t remember) (smile) umm, an inelastic collision is,

ok, an inelastic collision is a collision where two objects like collide, uuh

it’s not the same, the, the, amount of force or ah ah or what’s momentum,

the amount of momentum is not the same as when it started and … elastic

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is when it’s ah like conserved right?

Researcher: What is conserved-

Student 2: (Laugh)

Researcher: in an elastic collision?

Student 2: (Laugh) Ok, um, ……..(pause)…I am nervous.

Researcher: Don’t worry you do not need to be nervous (smile) there isn’t a right or a

wrong.

Student 2: I know what it is, but I can’t explain, I forgot the words.

Researcher: Ok, umm, there was something else; oh there was a B part-

Student 2: Um,

Researcher: Have you thought about it now?

Student 2: I think conservation of momentum is like, how can I put it now, it’s like … I

had it just now, (laugh) ….. xxx

Researcher: Think about it and then we will come back to it. Umm there is a B part of

the question, in the B part of the question there is a traffic officer at the

accident and he says that in head- on collisions, the passengers in the

lighter car usually get hurt more, and you had to explain using Physics

why that is so, why in a head-on collision the passengers in the light car

usually get hurt more. And you wrote: “the driver of the truck will take less

impact because of its size and mass, and the truck will make the car move

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in the same direction. Tell me more about why you think the truck will take

less impact because of its mass?

Student 2: I think it is because of the material which it is made of, it’s it’s, a car it’s

more like a, I don’t want to say plastic, because there are some parts, like

it’s made out of plastic, more than the truck, you know, it’s not plastic,

plastic, but you know that…, I don’t know that material it’s made off; and

the truck has more weight, you know there’s more stuff put on it and

because of the material as well, so when it collides it will move um the

car… the same direction as the truck was moving.

Researcher: Ok, you said that the truck will take less impact on its materials that it’s

made of, what is impact?

Student 2: Um impact is is the, (pause) for example, a car right, um, put it um,… ish,

ok, …, impact is the amount of force um, an object can take, but then, it

gets destroyed in a kind of way, like when it impacts, yah.

Researcher: So it’s the amount of force that it can take.

Student 2: Yah.

Researcher: Ok, so you are saying the, the, truck can take more force than what the

little car can take. Ok, umm, would you say Newton’s third law applies to a

head-on-collision? Newton’s third law says: “for every force there is an

equal opposite force. Do you think his law works in a head-on -collision,

that the heavy truck exerts the same force as what the light car does?

Student 2: No.

Researcher: Do you think it can’t work there?

267

Student 2: Yah.

Researcher: So … his law that says for every force there is a equal opposite force

doesn’t always work, it’s not really for every force?

Student 2: Maybe it can, but it doesn’t make sense.

Researcher: It doesn’t make sense?

Student 2: Yah.

Researcher: Why do you say that it doesn’t make sense?

Student 2: …Maybe it’s because of the explanation he has made …xx

Researcher: Does it not make sense from your experience point of view?

Student 2: Yah. It doesn’t make logic sense, to me.

Researcher: Ok, …um I was thinking of another place where Newton’s third law is

always used, for example the apple and the earth, the earth pulls the

apple down and the apple pulls the earth up, and Newton’s third law says:

“for every force there is an equal but opposite force, so the earth pulls the

apple down as much as what the apple pulls the earth up. Do you think

that’s right there?

Student 2: Yah it makes sense there that the apples mass is equal upward and

downward, and that the earth’s size has more influence on the gravity of

the, which pulls the apple down.

268

Researcher: So they have the same, there you believe that the forces are equal and

that the reason the apple falls is because the earth’s bigger?

Student 2: Yah.

Researcher: Ok…. Umm. The last question asked about modern multi-plugs, they

have a cut-off switch, you can actually see it over there, that little thing

sticking out. Umm, why is the cut-off switch so important, and you said

that: “the cut-off switch is important because once there is an overflow of

power into one plug and it is damaging your devices it is not

recommended if such a similar thing happens to pull the plug connected

because that can result in your death, because of the voltage power.

Therefore when pressing the cut-off switch it will allow you to remove the

plug, connecting any device, and avoid the fire." Why do you think, what

do you think will cause a overflow of power?

Student 2: I think if you put too many plugs in one, step-up and step-down, lots of

plugs can cause confusion.

Researcher: What is power?

Student 2: The amount of work that can be done.

Researcher: And what is the voltage, power that you wrote about?

Student 2: Electric voltage, human body is, what’s that word, it’s like a conductor as

well, not a weak conductor we can’t survive it, electricity and heat can be

transferred, too much heat causes our death.

Researcher: Are the plugs in the multi-plug connected in series or in parallel?

269

Student 2: Series.


Student 2: I remember something, it is easier can’t be room in parallel or a house

can’t be in a single row.

Researcher: (The researcher switched off the tape recorder and thanked the learner.)

N3: Interview with the third student on 12/08/2009 at 14h30-14h45

Researcher: In your worksheet you wrote that: “when resistor R in the diagram burns

out, then because the electric line is divided up into parallel line, the

voltage will stay the same, but the current will increase and the heat will

build up”, and the question was: “What will happen to the voltmeter

reading, so you say it will stay the same, but the current will increase and

the heat will build up, ok tell me more, why will the current increase when

the resistor burns out?

Student 3: Because the, in my understanding the resistor doesn’t actually work on

the, well it decreases the voltage but it doesn’t like decrease the voltage, it

just slows down the current so it’s like less harsh power or less, like if you

work on the voltage it wouldn’t be as effective as a circuit unit. So I figured

if it went then the ah, um, the , it went because the heat built up in the first

place, and if it went, then there is like no light bulb or like any other circuit

items to like, um, vent the heat and energy that’s in it. So like the current

would, I think I said, increase, so the current would increase because the

resistor like slows down the current and so if it’s not there it would like

increase the current.

Researcher: So you say that when that resistor burns out there is less resistance, that’s

270

why the current increases?

Student 3: Yes.

Researcher: Ok. Even though it is in parallel?

Student 3: Well, like I figured it is in parallel, like it splits, and if it burns out, then the

electrons would just find another route around, but seeing as it is not split

up any more they would move faster on one leg, like on one wire.

Researcher: How do you add resistors that are in series, let’s say they are a 10 and a

12 ohm?

Student 3: Well I know that if they are in parallel there is a little formula that I can’t

remember now, but if series then I am just going to add them.

Researcher: Ok, so the formula for parallel you can’t remember how that works?

Student 3: Umm you, you, take the ratio between the, the, them and then you add

them in the ratio or something like that.

Researcher: Can you try an easy one for me, let us say that you need to add 2 and 2, 2

resistors of 2 ohms in parallel and you need to add them, can you try and

add them. I can give you the formula, because that is given in the exam,

(researcher writes the formula on paper and gives it to the learner to try

the sum) try and see if you can add those two.

Student 3: (The learner does the sum and gets the correct answer of 1 ohm.)

Researcher: So you get 1 ohm, let me check your sum, yes it is correct, so 2 plus 2 is

1, so what does that tell you about adding resistors in parallel?

271

Student 3: Umm, that the total is a fraction.

Researcher: So it is actually less, if I had one two ohm resistor the resistance would be

two, but if I add another one the resistance goes down.

Student 3: Oh...

Researcher: So that that is quite weird if I have two in parallel and I take away one the

resistance goes from one to two, it actually increases when I take away a

resistor.

Student 3: Oh ja, then the current will decrease.

Researcher: Yes. Ok another question now, the one about the two cars bumping into

one another. The one car is standing at the robot and the other car comes

and bumps into it. The first question says that in certain collisions

momentum isn’t conserved, and then the question is: when is it not

conserved. In your worksheet you said that: "momentum will not be

conserved because energy is lost in the crash due to exchange into heat

and sound." Explain why you think momentum isn’t conserved when that

happens?

Student 3: Well momentum is like the product of mass times velocity, right? And

when it catches the, the, energy, the kinetic energy that the vehicle has,

when it catches it, not a lot, but some of it is lost, due like to conversion

into other forms of energy, um it will have like a small bounce and it will

deform the vehicle. I am not sure what linear momentum is, but I figure

that linear momentum is basically the same as momentum, and when it

like, it will, the energy of the truck would be lower after the crash because

of,...the producers of the cars produce the cars so that they do lose

272

energy during the crash, so that the momentum does go down, so it would

go down.

Researcher: So you say that the momentum would go down?

Student 3: Yes.

Researcher: Why do you think that it would go down?

Student 3: Because the, I can put the word impulse there as well because I don’t

know where it goes.

Researcher: Ok.

Student 3: But energy is lost you know and so it has to be lower.

Researcher: Ok, so tell me more about this energy is lost thing, you say that energy is

lost when it is exchanged into sound and heat.

Student 3: Yes, well no the energy doesn’t really disappear, it is converted, but it is

lost from kinetic energy, the actual kinetic energy of the vehicle is lower

after the crash than before the crash, you know.

Researcher: So because it’s changed you say that it is lost?

Student 3: Yes, in terms of kinetic energy.

Researcher: Ok, then in the B part of the question the traffic cop standing there says

that he has seen head-on collisions before and in head-on -collisions the

passengers in the smaller lighter car usually get injured worse and from a

Physics point of view why does that happen? So you (L3) said that “the

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reason it happens is that the light object has little momentum and when it

collides with a heavy object momentum is transferred between them. The

light object with the large momentum will now move at a higher velocity,

so the impulse of such a collision will be also more on a lighter object”.

Tell me why you think the light car has little momentum before the

collision?

Student 3: Um, because it has a low mass and like a light car it’s like a golf ball or

something when you catch it, it doesn’t have a lot of momentum you can

stop it with you hand or so. But when it gets bigger like a truck or so, like

even when you apply full breaks it still takes ten meters or twelve meters

to stop, because the mass is so large.

Researcher: So the little car has low momentum because of its low mass? Does

momentum only depend on mass?

Student 3: Um no, it also depends on the velocity.

Researcher: So if the car had a higher velocity?

Student 3: Then it would also you know have a high momentum, but, I figured that

seeing as it is a small car, small cars usually have small engines as well,

and a small engine can’t really let a small car go faster than a big car.

Researcher: Do you think that a small car could ever have more momentum than a big

car?

Student 3: In some cases yes… extreme cases.

Researcher: Explain to me why you think that the impulse will be more on the light

car?

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Student 3: Because the impulse is like the change in, the change in momentum, from

like before, and a light car will have low momentum before it crashes and

then when it does crash the, the, like energy which is transferred between

the two vehicles will increase its momentum and it will like, the shock will

be large, like the people on the inside will feel like a big force backward

and their necks will hurt or break or whatever, so the impulse, the change

in momentum will like be larger.

Researcher: How do you know that the people in the smaller car will experience a

bigger force?

Where would you say you got that idea from?

Student 3: Because, um, for instance if they crashed into a wall, a big one, not like a

small one, the impulse there will be very large because the wall doesn’t

have crumple zones and the wall would just direct all the energy back from

the car, like and then the car will basically just bounce off the wall, it has

its own small crumple zones, but a lot of bouncing is involved, and so

that’s the same with another vehicle, another vehicle just absorbs more

energy.

Researcher: So the wall would hardly experience any impulse?

Student 3: Um I think the impulse is the same but the wall doesn’t experience it,

because the wall doesn’t, it’s like strong.

Researcher: Ok, so you are saying that the impulse is the same?

Student 3: I think so, yes.

Researcher: Do you think it is the same for the small car and for the big car?

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Student 3: It might be I am not sure.

Researcher: Newton’s third law says that for every force or action there is an equal but

opposite force or reaction, do you think that applies in a head-on collision?

Student 3: Yes.

Researcher: Do you think the force of the big car on the small car is equal to the force

of the small car on the big car?

Student 3: Yes, it should be, I heard an example once where they said that when a

mosquito collides into a car the mosquito experiences the same force as

the car experiences from the mosquito.

Researcher: Do you believe that?

Student 3: I don’t know what they mean by that.

Researcher: Are they going to look the same?

Student 3: No, well, not at all. I don’t know what they mean, that the force will be the

same, because like, like to me it doesn’t make much sense.

Researcher: Ok, so you know the law, that’s why you are agreeing with it, but it doesn’t

make much sense from an experience point of view?

Student 3: Maybe if I had more equipment and stuff to measure it, then it would

make more sense, but from my limited experiences I don’t see it.

Researcher: Ok, thank you. Last question, (pause, while looking up the next question

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that the learner answered). In the hydro-electric power plant, the generator

converts 85% of the water’s kinetic energy into hydro-electrical energy, the

question is: what happens to the other 15% of the water’s kinetic energy

that doesn’t get converted into hydro-electrical energy. You wrote that:

“the other 15% is converted into other forms of energy, and that a

significant amount of energy get’s lost, the 15% of the kinetic energy that

is lost is lost due to friction, which is converted to heat and sound.” Explain

to me more about what you mean by this “energy is lost”?

Student 3: Um, like, when I answer questions like that I use things as a, like certain

parts of the question as a reference for, to my answer, and they asked

about the energy that could be converted into electrical potential energy

and kinetic energy, right? And from the perspective of kinetic energy,

energy is like lost into other forms of energy, you know, and um, like you

can’t really get sound back into kinetic energy, you know, well not with our

current technology, also not with heat, well heat a little bit, but not much,

you can’t get all the heat back into kinetic energy again. So in all essence

it is lost, but the energy still is there it just isn’t in your possession.

Researcher: Ok, there is a whole lot of Science vocabulary that we use, like kinetic

energy and momentum, impulse, sound, heat, etc. Do you think that

talking about energy is lost is Science terminology or every day

terminology? Have you seen it in textbooks or do you use it in the Science

class? Where would you say that wording came from?

Student 3: Well in Science class and the books and stuff, they never use it, they try

and steer us away from the term that it is lost, they try to tell us that it is

not lost, it is just converted and so forth, but for me to use, like, layman’s

terms and to explain the science behind it, to understand it better, I try to

explain it in things that are easy to understand, like lost and not converted.

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Researcher: Ok, thank you, and then how would you say does this idea of lost energy

match up with the conservation of energy?

Student 3: Um…

Researcher: Are you familiar with the law of conservation of energy?

Student 3: I think I know it, but …

Researcher: What do you remember about it?

Student 3: That in a closed system, I think it is a closed system, it’s a closed system,

or it’s a bouncy ball thingy, um in that system, it, it, if there is no friction

and stuff, then it would be conserved, right? But that can’t happen, like

you can’t have a closed system you know, because um normal things

can’t do that like you can’t get a little box and catch two things in there,

because something will happen, you know, it will absorb some energy.

Researcher: Thank you, that is all that I want to ask you, do you have any questions?

Student 3: No.

N4: Interview with the fourth student on 13/08/2009 at 11h00-11h15

Researcher: In your worksheet you wrote that: “this generator is a dc generator,

because of its slip rings.” Tell me more about the difference between an

ac and a dc generator.

Student 4: Ok, I don’t know. Um, ac, am I right, ac generators, …, dc generators use

electricity to create mechanical energy, I think, and ac generators, …, yah,

use mechanical energy to create energy, I think, I am not sure, cough, so

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what I think mam, is that because an ac generator is slip ring and a dc one

is, no a dc one is slip rings and an ac one is split rings, that’s what I mean.

Researcher: Would you say these in the diagram are spilt rings or slip rings?

Student 4: Slip.

Researcher: Have you done an experiment in the class, where you have built one or

have you seen an ac or dc generator?

Student 4: Experiment no; it’s what I saw from the textbook, slip rings...

Researcher: So pictures?

Student 4: Yes.

Researcher: The next question that you answered was the one about the cut-off switch.

These multi-plugs like this one over here, (researcher points to the nearby

multi-plug) has got a cut-off switch.

Student 4: Ok.

Researcher: So the question on the worksheet said: “why is the cut-off switch so

important?” You wrote that: “The cut-off switch stops the flow of power,

before anything harmful happens, because of the power getting too

intense.” What do you think caused the power to get too intense?

Student 4: (Pause). What caused the power to get too intense? Pause. Maybe

electric shortages or high voltage in the house system, I’m not sure, jah,

pause.

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Researcher: Ok, what exactly is power?

Student 4: Pause, well I think power is electricity and power is, pause, the ability for

us humans to live, the means to produce light, to see in the dark, to to

make food, yah, basically means of living.

Researcher: Ok, and then you said: “the cut-off switch switches off the power before

anything harmful happens”, what do you think causes the components to

get hot?

Student 4: The components to get hot? Umm. (Long Pause). The electricity, I think it

is the electricity, the flow of electricity. When not a specific amount is given

to it, when more than a specific amount is given to it then it gets hot.

Researcher: What do you think happens when I keep adding plugs, like that one can

take five plugs, but because I want more things in, I put a double adaptor

in, with more plugs, what do you think happens then, when I keep adding

plugs to that multi-plug?

Student 4: Well you are using more energy (voice very soft).

Researcher: Using more energy? (Verifying what I heard).

Student 4: I think you are using more energy than what the plug can really … give.

Researcher: And how would you say are those components connected? Are they

connected in parallel or in series?

Student 4: Think series, series.

Researcher: In series?

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Student 4: Series.

Researcher: If they are connected in series, what will they do to the total voltage that

the plug is giving them?

Student 4: I am not sure.

Researcher: Ok, one last question. The question about the car accident, where the one

car drives into the back of the other car at the robot, and the question

says: “when a heavy vehicle collides into a lighter car, the passengers in

the lighter car are more likely to get hurt”, and then you need to explain

why. In your worksheet you wrote that: “the heavier car has more weight,

thus resulting in the passengers in the lighter car having more injuries."

Tell me why do you think the weight of the car will cause more injuries?

Student 4: Umm, weight of the car, because, the weight of the car influences like the

force that the car exerts, so if a car is moving at a certain speed, and then

the lighter one is also moving at a certain speed too, then the, the, heavier

car tries to brake, it’s going to take longer for it to brake, because of all of

the weight on it than the smaller one, so then the heavier one is going to

exert more force than the smaller one, That’s why the smaller one has

more risk of getting injured than the heavier one. Force and the weight,

yah (very softly).

Researcher: Ok, what is the difference between weight and mass?

Student 4: Ok, weight and mass. Pause. Weight, pause I don’t know, don’t know, the

mass…

Researcher: Do you know what mass is?

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Student 4: The mass of the truck. Pause. 9,8 I think.

Researcher: Ok, what is your mass, for example?

Student 4: The one I measure on the scale? Cause that’s weight. Mass, (pause).

Researcher: When you get on the scale, what is the unit?

Student 4: (Pause). Won’t it be kg?

Researcher: Kg, so would kg be the weight?

Student 4: Pause. Think weight.

Researcher: Weight?

Student 4: Weight.

Researcher: That is all I would like to ask you, are there any questions that you would

like to ask?

Student 4: Yes mam.

Researcher: What would you like to ask?

Student 4: It’s about, cause mam gave me this question paper, (he looks through the

worksheet), it’s about these questions about current and dc generator, in

class we don’t do much exercises on them.

Researcher: Exercises or experiments?

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Student 4: Well experiments, the last time I did experiments on this was in grade 9,

what do you call, circuits and globes, and I don’t have, grade 9’s quite a

long time back compared to matric, it’s like three years back, and my

memory is kind of vague. So, could we like do some more, could as like in

chemistry when we do something we do an experiment to see what

happens, so that when we go and write it, the paper, we already know

what’s going to happen, how this reaction is going to be.

Researcher: It, is definitely true that we need to do more experiments, as a teacher

know the reason that we don’t, is time, we just run out of time, there is so

much that we still need to do, we always run out of time, so at the end of

the day, that is why we just try to get through the theory, even though we

know that you have to do the practical to be able to understand it, but

sometimes, you know, it’s the whole issue of time, so you don’t know what

is going to be the best , so in the end it is a judgment call, because you

need to do both, so you have to do the experiments, and you have to do

the theory, but then sometimes you think that because you have done the

experiments in grade 9 and now because you have to get the theory done,

and yes time is a very big issue. It’s unfortunately the problem, is the time.

N5: Interview with the fifth student on 13/08/2009 at 11h15-11h30

Researcher: This question asks: If R burns out, what happens to the voltmeter reading?

You said that: “When resistor R burns out, then the internal resistance will

decrease because there will be one less resistor working, so the voltmeter

reading will increase.” Explain to me why you think that when the R burns

out the internal resistance will decrease?

Student 5: Because then there is one less resistor. If there is less resistance, then the

current flows more.

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Researcher: Let’s move on to another question, there was a question about a cut-off

switch. In these multi-plugs there is a little cut-off switch, and the question

asks why the cut-off switch is that important, and you said: “the cut-off

switch prevents a power surge from damaging appliances and prevents

extra voltage from going through," what do you think would cause the

power to surge in the first place, to get too intense?

Student 5: Ah, pause. Lightning, or, pause. Or just if the power station is just, its

voltage is too high, or maybe if the like the transformer it is not functioning

or something.

Researcher: Ok, and what exactly is power, when there is too much power?

Student 5: Umm, pause, I usually see it as a, like too much voltage.

Researcher: Too much voltage?

Student 5: Ja.

Researcher: So the voltage increases?

Student 5: Mmm.

Researcher: Would you say those (researcher points to a multi-plug) plugs are

connected in series or parallel?

Student 5: Umm, pause. The plugs connected to the appliance?

Researcher: Yes, so basically the appliances, are they connected in series or in parallel

in there?

284

Student 5: Series.

Researcher: In series?

Student 5: Mm.

Researcher: Ok, last question, just one more. (Pause, while the researcher finds the

next question that the learner answered very expressively.) The collision

one, the car comes from the back and hits into the car at the robot, and

the question says in certain collisions linear momentum isn’t conserved,

when is it not conserved? And you wrote: "Momentum won’t be conserved

as the car’s shape will be permanently changed", explain why you think

the momentum isn’t conserved when that happened?

Student 5: ..Umm, because if it was conserved then the momentum after the collision

will still be equal to the momentum before the collision, and obviously

because there is change in form and heat and whatever, then obviously

momentum was lost.

Researcher: Ok, ah, you also wrote that momentum will be transferred to heat and

sound, like you said now, explain why you think momentum can be

transferred to heat and sound?

Student 5: Why?

.

Researcher: Auuh. Why do you think momentum can be transferred to heat and

sound?

Student 5: Umm.. I don’t really think it is the momentum I think it is the energy, the

kinetic energy.

285

Researcher: Ok, and then they asked: “When a heavy vehicle collides into a lighter car,

um, have I got your answer here ... yes, when the heavy car collides,

afterwards a traffic cop standing there says if a heavy car collides head-on

with a lighter car, the passengers in the lighter car are more likely to get

injured, from a scientific point of view why do you think this happens?

Student 5: Um…um well the heavy car has more mass so (long pause) um … and

also it won’t be, um like the lighter car has more, the chance of being like

hit to the side or something, because it’s lighter, while the heavier car is

more stable on the ground, because it is more heavier, and um,…, it’s

momentum should be actually higher because it has a higher mass, even

if they are travelling at the same speed, the truck still has more

momentum, so, ..

Researcher: ok, thank you very much, that’s it, all the questions, you did really well, do

you enjoy Science?

Student 5: Ja I do.

Researcher: Ok, obviously, you didn’t do as well as you normally do, because it only

was the explanation questions, and most kids do better in the sums,

surprisingly. Are you going to study something in Science next year?

Student 5: Nah.

Researcher: What are you going to do?

Student 5: BComm. Accounting.

Researcher: Aah, money, money, money, (laugh). Thank you very much.

286

N6: Interview with the sixth student on 13/08/2009 at 11h30-11h45

Researcher: Ok, so the first question I want to ask you about is this question about the

conducting wires, P and Q, so the question says you have two conducting

wires P and Q and you want to know which one is the better conductor. So

you put them in a circuit, you connect a ammeter near them and you

measure the current that is running through the two wires, and you

connect a voltmeter over the wire, to measure the potential difference

across the wires, and then you plot the data and this is the data that you

get (pointing at the graph on the worksheet), and from that data which

conductor is a better conductor, and why-y, how do you know which one is

a better conductor? Ok, you wrote: “wire P is a better conductor, because

it is at a higher potential difference than Wire Q.” Tell me more about why,

uhh, the higher potential difference would make it a better conductor. Why

do you think it works like that?

Student 6: Um... because, because of the high voltage the condu- um. I don’t really

have a reason for xx

Researcher: Why do you think you guessed that?

Student 6: Umm ... for some reason I think when something has the potential the high

potential difference it has the better conductor.

Researcher: Ok, what is potential difference?

Student 6: It’s the voltage of the umm … conductor or ...

Researcher: Ok, and what is voltage?

287

Student 6: Um, the measurement of umm xxx …aah …umm …can’t really think what

that is now um (pause)

Researcher: Ok, that’s fine. .. What do you think the current has got to do with the

conductivity?

Student 6: Uum that’s what the amount of... energy uh like flow of xxx ah ... what’s

the question again? (Smile)

Researcher: What is current, and what has it got to do with conductivity? Why do you

think they measured the current?

Student 6: I’m having such a blank now...

Researcher: It is there; somewhere, just think about it, what do you know about

current?

Student 6: … I know it has to do with the flow of electrons and all that xxx (Pause)

Researcher: Ok, so it’s got to do with the flow of electrons, so how would that affect the

conductivity?

Student 6: Um, the...actually if it has more currency it will be more conductive

because more electrons flowing -

Researcher: And which one -

Student 6: which would make it easier to -

Researcher: which one looks like it’s got more... current flowing through it?

288

Student 6: Um wire Q, that’s my answer but xxx (learner thinks about it)

Researcher: What do you think, now they have got both here, so they actually want you

to think about both of them, what do you think the gradient of this graph

would be?

Student 6: (long pause)

Researcher: Do you know how to work out the gradient?

Student 6: Yeah, that’s the difference in y over the difference in x.

Researcher: So what would it be for this graph?

Student 6: Um (pause) for the both?

Researcher: Yah, for either of them.

Student 6: Um (pause) I said wire Q’s gradient xx one…

Researcher: In terms of current and potential difference?

Student 6: Um, the current is more to the current (higher) and... wire P has more

potential difference so the (valence) is... lower or um nee I kan dit nie in

Engels sê nie.

Researcher: Jy kan dit in Afrikaans sê.

Student 6: Um, dit is minder (pause) um .. styg minder (pause)

Researcher: Ok

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Student 6: (kan nie help met die woorde nie)

Researcher: Ok ...kom ons kyk na ander vraagie.. antwoord jy gewoonlik in Afrikaans

of Engels?

Student 6: Uum, ek antwoord in engels, maar ons het eintlik tot in graad 10 in

Afrikaans geantwoord, partykeer dan sit mens n .. -

Researcher: Jy weet in die eksamen kan jy in enige iets...

Student 6: Ek weet nie, ons het gevra daaroor toe het hul gese nee as ons in Engels

skryf dan moet ons in Engels skryf.

Researcher: As jy sukkel in die eksamen-

Student 6: So ek weet nie hoe waar is dit -

Researcher: Kan jy enige iets, jy kan deurmekaar ook skryf.

Student 6: Aag ek het nie so groot problem met die (Afrikaans) dit is net partykeer

wat xxx dan het ek nie tyd om als oor te vertaal nie.

Researcher: Maar die merkers sal dit merk, so jy kan dit in engels skryf en dan as jy nie

die woord kan sê nie kan jy deurmekaar skryf, dit (word gemerk.) (Pause

while researcher looks for the next question in the student’s worksheet.)

Ok, hier was die ander ene, ok, uuh, dit was die vraag oor die kar, dit se

as die swaar kar, ah, in n ligte kar in bots dan gaan die mense wat in die

ligte kar sit heel waarskynlik, um, seerder kry, ah, en hoekom is dit so, ah,

ok en toe se jy: “both cars will be moving at a higher speed increasing the

amount of force that will be experienced.” So according to that why do you

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think if they are both going at a higher speed and are in a head-on

collision, and they both have a bigger force, why do you think the car, the

passengers in the light car will be hurt more?

Student 6: Um, (pause) well the die groter kar sal nogsteeds more force hê want die

massa en die spoed jah ..

Researcher: So dink jy hy gaan meer krag he?

Student 6: Ja di... altwee karre se force sal increase maar die groter vehicle se xxx

sal nogsteeds meer wees as die -

Researcher: Wat sal meer wees?

Student 6: Sy force?

Researcher: Sy impact force?

Student 6: Ja

Researcher: So sal hy die kleiner kar harder slaan as wat die ander kar hom slaan?

Student 6: Ja

Researcher: Ok,..hoekom dink jy so, hoekom sal hy harder slaan?

Student 6: Um.. wel dis groter oppervlakte eerstens wat … teenoor die kleiner kar

wat hy … meer area om te slaan en … as … die massa, as force massa

en accelerasie acceleration is, is sy massa dan meer is, gaan die force

ook meer wees, so (pause)

291

Researcher: En wat van die acceleration deel dan?

Student 6: (Pause) as .. as al twee karre … umm .. soos … word dit .. -

Researcher: Jy sê die swaarder kar gaan meer massa hê so sy krag gaan ook meer

wees, maar die krag is massa en versnelling, soo is jy seker dat sy

versnelling ook meer is?

Student 6: Oo, dit beteken nie dat sy versnelling gaan meer wees nie ,nie

noodwendig nie.

Researcher: Nie noodwendig nie, dan sal dit miskien die krag beinvloed?

Student 6: Nee, dit gaan net die krag beinvloed (dan sal die) krag dieselfde wees as

wanneer hy die stilstaande kar xxxx

Researcher: Ok, en dan ‘n ander ding nê, Newton se derde wet sê dat vir elke krag

wat uitgeoften word, is daar ‘n gelyke teenoorgestelde krag, so sou

Newton se derde wet hierso TEL, as die swaar kar die ligte kar slaan, vir

daai krag is daar 'n gelyke teenoorgestelde krag?

Student 6: …umm (pause) nee want daar .. of daar moet wees want dit maak nie

eintlik xxx maar ek kan eintlik dink waar..

Researcher: Hoekom sê jy daar moet wees, is dit omdat sy wet so sê?

Student 6: …Maar dit kan nie wees nie, want dit is nie geslote die (pause) die

(pause)

Researcher: Ok, so jy dink nie dit gaan daar werk nie?

292

Student 6: Ek dink nie dit gaan werk nie, want … dit gaan nie terug xxx dan gaan die

kar agter in xxx

Researcher: Ok, waar dink jy werk Newton se derde wet wel, wanneer is daar vir elke

krag ‘n gelyke teenoorgestelde krag?

Student 6: Wanneer daar niks anders is wat daarop in werk nie -

Researcher: Soos byvoorbeeld ek en hierdie tafel (researcher pushes her hand down

on the table)?

Student 6: Ja, dit gaan werk -

Researcher: Druk ons mekaar dieselfde hoeveelheid?

Student 6: Ja

Researcher: Ok, hoekom lyk die tafel se, jy weet ‘n tafel het geen misvorming, maar my

hand het, so die effek was nie dieselfde nie, al was die krag dieselfde nê.

Ok, dit is al wat ek wou vra oor daardie ene, nou nog eenietjie,

(researcher looks for the next question that the learner answered on the

worksheet) Wilma was hierso?

Student 6: Nee sy wag buite.

Researcher: Het julle klas nou?

Student 6: Ons onderwyser is afwesig.

Researcher: Daar is nog een vraagie wat ek jou wil vra. (Pause) Oh die lig, dit sê:

“when a laser emits red light and passes through a single slit a diffraction

293

pattern can be seen on a screen some distance away” en die vraag is:

“what does the diffraction pattern look like? En jy het geskryf; “the

diffraction pattern consists of red bars of light with dark bars in between

continuously with a central", dan kon ek nie lees nie, ietsie, “of red light."

Wat het jy gesê is daardie central?

Student 6: The central maximum.

Researcher: Ok, the central maximum of light. Umm. Het jy al ‘n diffraction pattern

gesien?

Student 6: Ek weet ons het, maar ek kan rerig nie meer daardie werk onthou nie,

maar ons het daardie diffraction patterns en daardie goed gesien.

Researcher: Het jul die experiment gedoen.

Student 6: Ja ons het daardie slits gebruik xxx.

Researcher: En jy kan nie mooi onthou hoe het hy gelyk nie?

Student 6: Um, dit was uh, dit was ok daai band bande maar ek kan nie mooi onthou

of dit equal uit mekaar was, of was dit groter spasies en dan kleiner

geword het nie, dit is wat my deurmekaar maak.

Researcher: Ok, en dan as jy die enkel slit met ‘n double slit vervang um hoe lyk die

twee patrone, wat is dieselfde van hulle, kan jy onthou wat was dieselfde

van die twee?

Student 6: Ek dink in ons boeke… (ek kan glad nie onthou nie) smile

Researcher: Ok (smile) So jy kan nie mooi onthou nie, as jy daardie laser sou vervang

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met ‘n gewone lig, .. , sou jy dieselfde patrone sien?

Student 6: Um ja want al wat verskil is die wavelength so nee maar dan sal hy

verander (pause) um (pause)

Researcher: Wat is die verkil tussen ‘n gewone lig bulb en ‘n laser?

Student 6: Um, die wavelength verskil van die (twee)...dit is ..

Researcher: Ok, baie dankie.

N7: Interview with the seventh student on 13/08/2009 at 11h45-12h00

Researcher: I forgot to put the tape-recorder on.

Student 7: Uuu because by crumbling it’s going to go slower, it’s going to lose …

the... if the F = I/g or something (Laugh) I’m not sure…

Researcher: Ok, it’s fine.

Student 7: You are going to lose F so the I will also become (less) but that’s xxx (it

depends)…

Researcher: Ok.

Student 7: I don’t know.

Researcher: Ok, umm, what would you say.... what exactly is an elastic collision, what

is the difference between an elastic collision and an inelastic collision?

Student 7: Ek dink ... I get umm confused between when it is elastic and when it is

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closes the circuit (but) I think elastic is something when something like a

snooker ball almost no momentum is lost there because it is smooth

…and no outside forces … is there to kind of slow it down ..xx

Researcher: Ok, that’s fine and there is another part of the question, the b part of the

question that says: “If two cars collide head-on, there is a light car and a

heavy car colliding head-on then the passengers in the light car will be

less likely to get hurt” … and then you had to say why, why was it like that,

and you said: “ the heavier car will have more momentum so it will keep

going in the same direction but slower , when the lighter cars direction will

change because it’s passenger keeps going the same way so it’s

passengers will experience more force.” For how long do you think the

passengers will keep going the same way, so you said the heavier one is

going to hit then the light one is going to have to change direction it was

going this way (researcher points at the picture of the car on the

worksheet) so it is going to have to change direction, but the passengers

won’t they just keep going forward because of their momentum, for how

long do you think are they going to keep going forward?

Student 7: Just like a few split seconds and then they will be pulled back.

Researcher: Ok so and why will they experience more force?

Student 7: Because they will be moving…it won’t just be force from the front…they

will be moving…in the direction where the force is coming from, so like in

xxx

Researcher: Ok, so because they are going in the opposite direction they are going to

experience even more force.

Student 7: Mm.

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Researcher: Um, Newton’s third law says that for every force there is an equal but

opposite force, do you think that works in a head-on collision like that, will

the force that the heavy truck exerts on the light car, do you think the light

car exerts the same force ?

Student 7: Yes, but the heavier car has even more force.

Researcher: Ok, so the heavier car has even more force?

Student 7: xxx

Researcher: Ok, another question (researcher briefly looks for the next question that

the learner answered on the worksheet.) These multi-plugs (researcher

points at a multi-plug) they have a cut-off switch, why is the cut-off switch

so important? Um, you wrote: “it is important because when current flows

through a conductor, the conductor heats up, if the current is too high, the

wires will burn out.” What causes the current to become too high?

Student 7: The…you mean like if the electrons move it would xxx

Researcher: You said that when the current flows through the conductor the conductors

get hot, and if the current is TOO high then they get too... then the wires

will burn out and that is why you need a cut-off switch. So what would

cause the current to become too high in the first place?

Student 7: If you use too many appliances…in the one like sock-et

Researcher: Mmm. Then the current would get high higher?

Student 7: Yes.

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Researcher: Why do you think it works like that, why do you think the current gets

high? You are right it does get higher, but why?

Student 7: Because it needs to be more places at once.

Researcher: Ok, are those resistors, appliances connected in series or parallel when

you put them in a multi-plug like that?

Student 7: (Pause). Probably series.

Researcher: Why do you think series?

Student 7: (Pause) Because if the..the one appliance breaks the others will still keep

going even though…-

Researcher: So of the one appliance breaks the others can keep going, does that

mean they are in series?

Student 7: …Yes, because then there is no …the circuit isn’t broken there is still

somewhere for the electricity to go ..to the other appliances.

Researcher: Ok, another question, last one. (Researcher looks up next question that

the learner answered on the worksheet). It’s about the laser. The laser

emits a red light and it passes through a single slit and then you get a

diffraction pattern on a screen. What does that diffraction pattern look like?

Ok, you wrote that:”It consists of a bright central band of light with (clear

throat) bands of on both sides, it becomes smaller and dimmer the further

they are from the centre.” What do these bands look like, that become

smaller and dimmer, what do they look like, what colour are they?

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Student 7: Well it’s red and then it’s like black with no colour, and then the red will be

there again but it will be..it wouldn’t be as intense anymore it will be darker

red and darker darker xx

Researcher: Ok, and what do you mean by the bands become smaller?

Student 7: The middle band will be like the bigger piece and space where the red’s

shining and then there will be bigger bands next to it, and then the next

red band won’t be as wide as the middle one and then …(laugh) get

narrower, narrower…

Researcher: It becomes narrower and narrower?

Student 7: Mm

Researcher: Ok, um if they replace the single slit with a double slit, then the pattern

looks different in some ways and similar in some ways. What are the

similarities between the pattern with the single slit and the pattern with the

double slit, what is the same about them?

Student 7: They still have alternating bands of colour and black no colour.

Researcher: And what’s different about them?

Student 7: Um the double slit...the bands will stay the same length apart because of

the wavelength and the same length apart when they cross each other, so

the pattern will just go on …

Researcher: Ok and if you had to replace the laser with a normal light bulb, would you

see those patterns?

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Student 7 .Yes but the light bulb wouldn’t...there…some of the light would be lost

because it’s not like this … straight piece of light, it won’t be as bright, you

are not going to have as much light and it’s going to be a different colour.

Researcher: Ok, thank you, that’s all I wanted to ask. Thank you.

N8: Interview with the eighth student on 14/08/2009 at 11h00-11h15

Researcher: Ok, I am just going to ask you three questions about what you wrote in the

worksheet. The first question is: “A fully automatic camera has a built- in

light meter. When light enters the light meter it strikes a metal object that

releases electrons and creates a current.” And then the question was:

“What happens to the energy of the emitted photo-electrons if the incident

radiation is increased, while maintaining a constant wavelength?” Ok, and

you wrote: “The energy of the emitted photo-electrons increases, as the

intensity increases.” Why do you think that the photo-electrons’ energy,

because they are asking you what happens to the energy of the photo-

electrons when you increase the intensity of the light, why do you think

that the energy of the photo-electrons increases?

Student 8: Ok, honestly, that answer I did not know, so I was like if I write this maybe

I will get one mark or so. I didn’t understand the question, and I didn’t

know the answer at all.

Researcher: Ok, so you can’t think of a reason may be why you guessed that?

Student 8: No. (Laugh)

Researcher: Ok, um. Then there’s another part, ok, what do you think it actually means,

in the question they say: “The intensity of the light increases, but the

wavelength of the light stays the same.” What would you think it means

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when they say the wavelength of the radiation stays constant?

Student 8: Ok, ask the question again, please (laugh).

Researcher: The intensity of the light that hits the light-meter is more, but it’s

wavelength stays the same, what do you think that means, what does it

mean when the wavelength stays the same?

Student 8: (Pause)

Researcher: What is wavelength?

Student 8: (Pause) (I have no idea)

Researcher: If you had to take a guess, if you had to explain it to a friend …what would

you say wavelength is?

Student 8: (Laugh) I don’t know um... The wavelength would be something ok xxxx

(laugh). Inside the light bulb, is this the light?

Researcher: Ja, the light xx

Student 8: Ok, I think the wavelength is the ...amount of time it takes for a person to

see the light on the outside (pause) transmitted from the inside of the light.

(Pause)

Researcher: Ok, and then there was a B part, they said that um: “What would happen

to the number of photo-electrons emitted, if the intensity increased, and

why would it happen?” So you are shining light with a bigger intensity on

the light- meter, what happens to the number of photo-electrons emitted,

and you wrote that: “The number of photo-electrons would increase", um,

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which is right, but you need to explain why, why do you think that number

of photo-electrons will increase when you increase the radiation, why do

you think that it would increase?

Student 8: I just thought that if the radiation increases, then the what is it?

Researcher: Photo-electrons?

Student 8: Ja, the photo-electrons would, you know what, this whole question I just

guessed, so… no I didn’t guess actually, but I just thought that, my brain

just told me I should write that it increased because of the radiation

increasing .

Researcher: Ok, um have you seen a light-meter or a photo-electric cell?

Student 8: MmMm

Researcher: Neither of them, you have never seen a photo-electric cell?

Student 8: MmMm

Researcher: A picture in a book, in your science textbook is there a picture of a photo-

electric cell?

Student 8: Yes, there is.

Researcher: Can you remember what it looks like?

Student 8: No, (smile) (laugh)

Researcher: Can you remember when you did this section?

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Student 8: Last term, no no no no, first term, if I am not mistaken.

Researcher: The first term, ok, (pause) ok, where did you get most of your ideas on the

photo-electric effect, you can’t remember much about the photo-electric

effect, the experiment or anything?

Student 8: No, no, I can’t remember.

Researcher: Ok, thank you, let’s try another question. (Pause) The light one. Um,

“When a laser emits red light and it passes through a single slit then you

get a diffraction pattern on a screen. What does that diffraction pattern

look like?” Ok, um you said: “There will be central maximum, and the rest

of the light will spread out.” Tell me more about what you mean, because

you have got there’s a central maximum, but if I’ve never seen this, I have

no idea what a central maximum is, so I don’t know what it looks like, so

what does a central maximum look like?

Student 8: Ok, when the light goes through the slit, there’s a, a broad band right and

then, ok I can’t remember if it is a double slit or single slit that does this,

but there’s, ah..the bands are evenly spread out towards either of the

sides of the central maximum.

Researcher: So the central maximum is a band of light, what colour is it?

Student 8: It’s black. No mam, white...ja it’s white.

Researcher: White …and um how broad is the band, compared to the other bands, are

they all the same size or what?

Student 8: Well with, Ok, there’s two, there’s a double slit and there’s a xxx uugh a

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single slit sorry, and it depends on which slit you use to direct the light, but

now I remember there was either one with a broader central maximum

than the other one, and then there was aah they were evenly spaced out,

in the double slit I think, the the xx was evenly spread out.

Researcher: Ok, what was the difference between the single and the double slit?

Student 8: Um, I think it’s the way the, the bands are spread out. ..Ah the one has the

… -

Researcher: The double slit, how does the double slit look like?

Student 8: I’m just going to say both; I’m not going to put a name to either. The one

the central maximum, from the central maximum the other bands are

spread out, I think (pause) I think it was a bigger spread than the other

one, I think so, and then (pause) mm now I can’t even remember, but then

all that I remember is that the spaces weren’t even in the one and in the

other the spaces were even.

Researcher: And you don’t remember in which one?

Student 8: MmMm, I think it’s the double slit.

Researcher: The double slit they are even spaced?

Student 8: Even spaces, ya.

Researcher: Do they both have that central maximum?

Student 8: Yes.

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Researcher: And all of this pattern is it all just black and white, or what does it look like?

Student 8: It’s black and white.

Researcher: Not red?

Student 8: (Pause) (Smile) (Maybe it’s red.)

Researcher: Did you see it?

Student 8: Yes I did see it.

Researcher: You did the experiment?

Student 8: Yes we did the experiment.

Researcher: Ok, um, then they asked: “If you had to do the experiment without the

laser, if you didn’t have the laser, you used a normal light bulb to do the

experiment would you see the diffraction pattern?” that you normally see

with a light bulb?

Student 8: I don’t think so.


Student 8: Because the light in a light bulb isn’t as strong as a laser, because a laser

shines directly, the light bulb just … the light bulb just … it’s just a general

light, and then the laser shines directly through.

Researcher: Do you know what the word for that is, for shining directly?

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Student 8: Umm, …,no. (laugh)

Researcher: It’s coherent.

Student 8: Ok, (smile)

Researcher: Ok, last question, umm it’s this one. The question with the two car’s that

bump into one another and they said: “During a, in certain collisions

momentum isn’t conserved, when is linear momentum not conserved?”

You (L8) wrote: “The linear momentum isn’t conserved when both cars

move forward after the collision and the one car moves even further

forward.” Explain why you think momentum isn’t conserved when that

happens?

Student 8: (Pause)

Researcher: Why is momentum not conserved when they both move forward and the

one moves even more forward?

Student 8: Isn’t ah conservation of momentum when a car after collision stops, isn’t

that xxx that’s what I understand, like both the cars, like if the one car is

coming and …

Researcher: The one was just standing still and the other one was coming from the

back.

Student 8: So I would, did I write that the second car …

Researcher: Ok, you just wrote, um, let’s just find it exactly here (researcher looks at

the learner’s worksheet answer) you wrote: “It may not be valid that linear

momentum is conserved because both cars move forward after the

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collision, and car A moves even further forward, meaning that the

momentum is not conserved and the circuit does non conservative forces

such as force.”

Student 8: Ok, ah, (pause) (What was?)

Researcher: Why do you think that if they both go forward after the collision,

momentum is conserved?

Student 8: Because ah, I understood from conserve aah conservation of momentum

was that the car after the collision stops, ug… wherever it lands up it just

stops, and that’s what I thought.

Researcher: Ok, um, you said here that um “in a circuit there may be non conservative

forces such as force", tell me more about these forces that would hinder,

you are saying that they are non-conservative forces that are going to

hinder the conservation of momentum, what are these forces that would

stop the conservation of momentum?

Student 8: Aah, did I say force here?

Researcher: Ja, you said the circuit has non-conservative forces such as force.

Student 8: Ok, …last term I think we learnt about non-conservative forces, but I think

I got this section mixed up with another section, so I think the force the

non-conservative forces, I learnt about another one and then I mixed them

up and then I just was confused mam, ya.

Researcher: Ok, so you are not sure.

Student 8: Ja, I am not sure.

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Researcher: Ok, are there any questions that you want to ask me?

Student 8: (Shakes head no)

Researcher: Ok, I am going to give your paper back to your teacher, I will give her a

photo-copy of that, and there is just one thing that I want to explain to you,

because I didn’t tell you anywhere where you were right or wrong or

anything and I am not going to, except this one thing I am very tempted to

tell you, because you said you got the idea that momentum is conserved

when they stopped afterward, in this situation you had the one car that

was standing still and you had the other car that was moving forward so

before the collision there was momentum in the forward direction because

of the one car that was going forward, so if momentum is conserved,

which means it stays the same, then it means that you must have some

type of momentum afterwards, because the one car was moving forward,

so there was momentum forward so that means afterwards there must be

momentum forward, and for it to be conserved it must be the exact

amount, so that’s why there must be some kind of movement afterwards

because ...if they stop during the collision then it wouldn’t be conservation

of momentum, because you had momentum before that means you must

have momentum afterwards. When they stop it means, if they stop after

the collision then it means that the momentum before the time had to be

zero, now how would that have happened, they wouldn’t have collided into

one another if they were standing still, the only way that their momentum

before the time could have been zero is if they were moving in the

opposite direction because then their momentums are in opposite

directions, and they cancel one another out in a head-on collision, and hey

they have to have the same momentum before, or them to cancel out

exactly and to stop. Sometimes you have head-on collisions and they

don’t stop, but that doesn’t mean that momentum wasn’t conserved, it just

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means that if they go that way then that one will have more momentum,

not necessarily faster, more momentum can be faster or heavier, -

Student 8: Ooh,

Researcher: because momentum depends on mass and the velocity.

Student 8: Ooh, ok. Thank you mam.

N9: Interview with the ninth student on 14/08/2009 at 11h15-11h30

Researcher: There it is (referring to the learners’ worksheet) the one that you signed.

Student 9: Ja

Researcher: Umm

Student 9: That’s me.

Researcher: This is you. Ok, let’s find where you wrote that, ok I’m not going to show

you your marks now; otherwise you are just going to be worried.

Student 9: No, I won’t be worried, (aagh who cares.)

Researcher: It’s just the explanation questions and most kids do worse in the

explanation questions. Ok, so that is why I am doing the explanation

questions. Umm, actually it’s weird you do better in the sums-

Student 9: Mmm

Researcher: -than in the explanation questions.

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Student 9: That’s because it’s straight forward, you know the formula and you just do

it.

Researcher: Ok, right the question says: “When a laser emits red light and passes

through a single slit, then you get a diffraction pattern-

Student 9: Jaa

Researcher: -what does a diffraction pattern look like?” Ok you wrote umm, now I am

looking at the wrong question-

Student 9: Jaa I remember answering that.

Researcher: (pause as researcher looks for the learners’ answer for the question from

the worksheet)

Student 9: Did you type out all our answers as well?

Researcher: I haven’t yet; I’ve still got to do that.

Student 9: Aah whew, it’s a big project.

Researcher: Ok, there’s the circuit (pointing to the circuit on the worksheet) and they

said: “If that resistor burns out, what will happen to that voltmeter

reading?” Ok, you wrote: “If that resistor burns out, the voltmeter reading

will increase-"

Student 9: Jaa

Researcher: -which is right, " because there will be less resistance in the circuit.”

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Student 9: Yes.

Researcher: So first tell me if that one burns out, why will there be less resistance in

the circuit?

Student 9: Because there’s one less resistor (smile).Ok (laugh).

Researcher: That sounds pretty obvious. Ok, if there’s one less resistor so the whole

resistance has dropped, why is that going to make the voltmeter reading

go up?

Student 9: Because, if there’s less resistance then obviously there’s more power that

goes through the (stream) instead of if there were two resistors then,

obviously it uses more of the volts so if you can say, I don’t remember all

of this work anymore (Laugh), but I kind of figured, you know, if there’s

more resistance then the voltmeter reading would be less, because the

stream has to do more work when it moves,..or the power..electricity has

to be xx

Researcher: Ok, what does a voltmeter read, what does it actually measure?

Student 9: I know the Afrikaans word.

Researcher: Ok, tell me.

Student 9: Stroomsterkte.

Researcher: It measures stroomsterkte, the voltmeter?

Student 9: Ja.

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Researcher: Ok, so stroomsterkte in volts?

Student 9: Ja.

Researcher: Ok-

Student 9: AAH, that’s the ammeter!

Researcher: Mm, ok, so what does the voltmeter read?

Student 9: Potential difference or something.

Researcher: Ok, potential difference, what is potential difference?

Student 9: I have no idea anymore. (Laugh)

Researcher: Not sure at all what it is?

Student 9: AAH, it’s something to do with the batteries or ..I don’t know um,…

Researcher: Not sure what the potential difference is?

Student 9: No.

Researcher: Because the voltmeter reading does go up, but it’s not because…

Student 9: Why does it go up then?

Researcher: I will tell you now now.

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Student 9: Ok.

Researcher: Let me see where there was another question that I wanted to ask you. I

think that what it, ok, let me just check your other questions because I will

come back to that one now. The other question was, these multi-plugs that

you get, (pointing to a multi-plug) they have got cut-off switches, those

little cut-off switches over there (pointing to the cut-off switch on the multi-

plug).

Student 9: I didn’t have an idea what a cut-off switch is.

Researcher: Here it is (pointing to the cut-off switch on the multi-plug) you can push

that thing then it cuts off.

Student 9: So there’s no electrical flow.

Researcher: Yes, and they said: "why is it so important?", so you wrote: “It enables us

to stop the circuit from flowing through that plug and it cuts-off the circuit."

(Learner starts laughing quietly).

Researcher: Why is it so funny? (Smile)

Student 9: (Smile).

Researcher: Why do you think the cut-off switch NEEDS to cut off the circuit in the first

place?

Student 9: If there’s a overload of plugs or … in the plug…

Researcher: Overload of plugs, what is an overload of plugs?

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Student 9: Well, too many plugs using too much energy, electricity.

Researcher: Ok, and what happens then?

Student 9: Then something can blow a fuse, you know and (pause)

Researcher: Ok, why would they use more electricity, what would they use more of …

when you put too many plugs in there?

Student 9: (Pause) Well I think..I don’t know … maybe if you use different.. machines

or things that use a lot of power, and so it has happened before in our

house that the plug just wanted to blow up, because it was too much

friction or.. I don’t know? Power.

Researcher: What do you mean by power?

Student 9: Electricity. (Smile)

Researcher: Electricity. What do you mean by electricity? (Smile)

Student 9: The flow of electrons (smile)?

Researcher: So the flow of electrons becomes more?

Student 9: Yes, it becomes too much.

Researcher: It becomes too much.

Student 9: Mm.

Researcher: How are they connected, would you say, it that series or parallel?

314

Student 9: (Pause). I think it is series.

Researcher: Why?

Student 9: (Pause). I don’t know (Laughing) because they are in line there?

Researcher: Because they are in line?

Student 9: Ja.

Researcher: And that’s all I want to ask you, so let me go back and (researcher

switches off the tape-recorder and continues to explain the question the

learner asked previously, the one that the researcher said they would

come back to after the interview.)

N10: Interview with the tenth student on 17/08/2009 at 11h00-11h15

Researcher: I’m just going to ask you about three of the questions that you answered.

The first question that I am going to ask you about is the question about

the hydro-electric power station ... and uh in the hydro-electric power

station they say: “The water runs down and then about 85% of the waters

kinetic energy gets transformed into electricity, so what happens to the

other 15% that doesn’t get transformed into electricity?” So you wrote that:

“the other 15% is lost through other things such as heat, movement,

sound, etc.” Explain to me more about what you mean when you say the

energy is “lost”.

Student 10: When I say the energy is lost, I mean ... uh through when it was

transferred from the … what do you call it, xxx, yes, it was lost through,

they go through pipes right? Ja, and when they went through the pipes not

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the exact amount that was, the initial amount was not the one found at the

end, and the reason I came up with the fact, it could evaporate, it could be

lost through heat, vibrations, it could be lost through a lot of things, that’s

why I said etcetera, that’s what I understood by it.

Researcher: Ok, where would you say you got the idea from that energy is lost?

Student 10: Energy is lost, when we did xx, and let me think, when we did reactions,

that’s Chemistry, so I thought, ok, that happens when they ask you :”

where did the rest of the energy go?” and then you say electrons are lost

or they are gained, so I just took it from that..

Researcher: Umm … does this idea of lost energy match up with the law of

conservation of energy?

Student 10: (Pause.)

Researcher: Are you familiar with the law of conservation of energy?

Student 10: Yes. Energy not being destroyed or... ?

Researcher: Yes.

Student 10: But it can be transferred, yes it can be transferred, it does match up.

Researcher: And lost?

Student 10: Lost? No it doesn’t quite match up with it, lost, but the whole transferred to

from something else to another, like the initial amount to where it is lost

through heat…

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Researcher: Ok...ok let me find another one that you answered-

Student 10: It was probably transferred, ja, it can’t be lost.

Researcher: So you say it is transferred not lost?

Student 10: Yes it is transferred. It’s transferred not lost.

Researcher: (Cough) Ok, then this question, you have the two parallel plates um and

they say:” this is the way that a printer works” and basically the ink droplet

comes in, and the ink droplet has been negatively charged, and when it

comes between the parallel plates, it gets attracted upwards, so “what is

the charge on this bottom plate?”, so the ink droplet is negative, what is

the charge on plate B? You said um that: “Plate B is positively charged,

due to the fact that the negative and positively charged ink droplet will

work together to produce ink on the paper.”

Student 10: (Laugh)

Researcher: Tell me more about how this works. (Smile)

Student 10: Mam, that was much of a guess ... I seriously and honestly didn’t put any

applications into this question, I just … it was more of what I was thinking

...yes I I seriously, even now don’t understand why… that is so…

Researcher: Ok, so you’re not, you don’t know why you’re thinking that it’s positive,

why have you got the feeling that B is positive?

Student 10: That B is positive?...um I I have a … that if it’s negatively, uugh I have a, I

just guessed that if it’s negative then the plate at the bottom will be

positive, cause I just assumed that this line that’s the separation, I just

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took, like oh that’s positive and that’s negative, it was more of a guess, it

didn’t have any applications that we did, it was more of a guess.

Researcher: Ok, What do you know about how opposite charges react, if this was a

positive plate like you said, and that’s a negative, what do positive and

negative normally do, positive and negative charges?

Student 10: Usually uh they work together to produce whatever, and then negatively

and negatively, it’s the whole repelling and attracting.

Researcher: Ok, so would you say opposite charges attract or repel?

Student 10: They attract.

Researcher: They attract?

Student 10: Yes.

Researcher: So if this one was positive and the charge was negative, which way would

the droplet move?

Student 10: It would move this way?

Researcher: Which way, up or down?

Student 10: Down.

Researcher: And it hasn’t done that hey?

Student 10: Yes.

.

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Researcher: So what does that mean do you think?

Student 10: (Smile). It divides up.

Researcher: Why do you think it divides up, instead if they are attracting one another?

Student 10: Uuh, that means that it doesn’t necessarily work the way that charges, I

think that charges work.

Researcher: If B was negative and the ink droplet was negative then what would they

do, what would the two negatives do?

Student 10: They would repel and it think it wouldn’t, it would go straight or it wouldn’t

work at all I think.

Researcher: If they repel, which way would the ink droplet move?

Student 10: Umm, I will take a wild guess, I think it will go straight or go the other way.

Researcher: Ok, ok… last question. This one was about the light meter, a camera has

got a light meter in, to measure the intensity of the light, and the way it

works is that, you shine the light on it and then there’s a metal object that

releases electrons and creates a current, which makes the meter give you

a reading. Umm (cough) in the question they asked: “What happens if they

increase the intensity of light, without changing the wavelength of the light,

they just increase the intensity of the light, what happens to the energy of

the electrons that are emitted?” -

Student 10: If they increase the?

Researcher: If they increase the radiation, in other words the amount of light.

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Student 10: But they don’t increase the?

Researcher: They don’t change the wavelength, they just increase the radiation. What

is going to happen to the energy that the little photo-electrons have got

that are emitted.

Student 10: Isn’t it going to be more?

Researcher: Ok, you said, I think that is what you said, you said: “The energy of the

emitted photo-electrons will increase and then return to its original energy

level and will have a new born or gain electron during the energy transfer

of energy.” So explain to me why do you think that when they increase the

radiation the energy of the photo-electrons increases?

Student 10: Well I, I uh, remember the whole photo-electron when they say um,

something about when you increase … I think the energy or something,

and then another one is xx created on the way, I can only draw that, I am

more practical, I can draw that and explain like that, just like you increase

the radiation but the wavelength is the same, but it’s going to change the

photo-electrons, there is going to be more, that’s what I understand, I think

I can explain on paper.

Researcher: Ok, do you want to explain on paper?

Student 10: Remember the whole. (Learner starts drawing a diagram on the

worksheet)

Researcher: Is it working? (Referring to the pen)

Student 10: Yes it’s working. There was the whole (continues drawing) I can’t

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remember exactly, it looked like a capsule I think, and there was

something about, I think when energy increased? Or something, along the

way a new electron is, is born, and then they increase so that’s why I said,

ok I can’t remember, can’t really explain it, can’t really explain why…

Researcher: What do you mean by: “a new electron is born?”

Student 10: (Pause) There was this other one that I read, before I read this because

xxx photo-electrons, and I remember it saying something when you

increase the energy or something like that a new electron is formed, that’s

what I understood by it, that’s why I say it will increase, does it increase

the radiation?

Researcher: Ok, ok ...that’s all … have you seen a photo-electric cell or a light- meter?

Student 10: Yes but only on paper.

Researcher: Only on paper?

Student 10: Yes.

Researcher: Ok, so in your textbook basically or a picture somewhere?

Student 10: Yes a picture.

Researcher: Ok, that’s all, are there any questions that you want to ask me?

Student 10: Yes I want to ask you mam, um Science this year it’s tough, (smile)so

mam I was just since while you are interested, well I think you want to

help, yes, since well you’re going to help , I am suggesting that we should

go, you know going through papers it’s more like these days you just get

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the same questions and then, you like, kind of like store it in your head, we

don’t really sometimes understand what’s happening and what… what’s

going on we just store it, and oh I remember reading something about this

so I’m just going to say this, and its more about that, and it’s really bad so

that’s why I, cause I really understand xxx

Researcher: So you mean going through a lot of exam papers gets boring?

Student 10: It does.

Researcher: And then you don’t really understand it anyway?

Student 10: I only understand the chemistry this year, it’s nice, but the Physics part…

and it’s not only me (my friends …) I didn’t understand this… well.

Researcher: Ok… ok thank you. (The researcher then put the tape-recorder off and

attempted to give the learner advice, without interfering. The researcher

also informed the learner that her teacher would be returning their

worksheets with an extended memo to them.)

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Appendix O

Transcripts of teacher interviews

O1: Interview with the first teacher – the Head of the Department – on 14/08/2009

at 9h15-9h45

Researcher: Right, there are no right and wrong answers it’s just your opinions.

Teacher 1: Oh, ok.

Researcher: Ok, so the first question is: tell me in your experience with the learners in

your class, how common are learner’ misconceptions?

Teacher 1: (Pause) Very common, I think um especially in the earlier grades, if I take

in my case with Life Sciences, if you take the grade 10 learners and you

have to work towards matric and you are teaching them different things,

like the grades 10’s you still battle because they really, the level of

understanding and the language ability is very poor at times, but then if

you work with them by the time they are in matric I am quite happy with

them, yah..

Researcher: Ok, How do you think learners develop misconceptions?

Teacher 1: (Pause) whew I still think that um there is a language thing involved

because they, they just do not sometimes understand what you are

explaining to them, because it’s not in their world, um, they don’t know,

you know we take it that they all have experience and that they all read

and that they all have general knowledge, and these days they have very

little general knowledge, and they’re also not interested to read or to look

at programs that will develop them, nothing like that, so I think

misconceptions, but maybe also if you do not teach properly, I have found

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that sometimes you will just explain something very quickly and then do an

exercise on it and the answers that you get tells you gosh they didn’t

understand a word you said, so you have to re-teach that, um, with time I

have seen that many teachers do that, I do go back and do it (smile). I

think it is a very, with both, but to me the learners, uugh, the interest level

is very low at times.

Researcher: From your point of view what would you say are the main sources of

learner’ misconceptions?

Teacher 1: (Pause) Umph Gosh you give me difficult ones (smile)

Researcher: (Laugh)

Teacher 1: Main sources of learner’ misconceptions. (Pause) I would say um

…improper maybe preparation beforehand that you just fire away that you

teach them something that you did not really prepare the basic concepts

enough, In Science very often they come and they have no basic

concepts…and you fire away like with electricity in a certain and you just

do that, they have no idea really, you know they still think that it comes

from a pole, ...so um I would say teacher preparation before hand to really

find out what they know…and to prepare them ..ah to go back I think that

is one of your big things …um …um…ja… and then ja ..I can’t think of

anything else now ... xx sources, and of course the reading, ooh the

reading level that is a big problem with some of our learners they, they just

cannot read and they also cannot hear. You can explain something very

basically to them and you ask them: "repeat what I’ve just said to you" and

there’s just no ability to take in what you’ve said ...uuh... (Background may

be a big problem)…

Researcher: Um. How would you define a misconception?

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Teacher 1: A misconception. (Pause) Ah to me a misconception … not understanding

what exactly um a specific thing implies …or misunderstanding, having a

complete different picture of a certain concept, …, because I have often

found you know, you know what the concept is you know what the

definition is, but sometimes the interpretation is so different to yours and

they actually teach you about it and it is like wow I never thought you

could look at it that way. So a misconception I just think it is changing the

complete idea of what something is, or not understanding it completely.

(Pause)

Researcher: Ok, um. What strategies do you use or have you tried which may remedy

learner misconceptions?

Teacher 1: (Pause) Well everything. Uuh…ok…I’m still dreaming of my projector to

come in, because I’m sure if you can show them certain of these things it

will help a lot. I have tried everything, if I have a child that does not

understand, firstly you have the class where you teach, where you explain,

still no understanding I sit one to one with that child, I really do make time

to do that, even whilst they are busy with work in class I will sit with that

child and see if I can get them, still nothing then I will go home and think

about it and start with other sources, pictures..um practical things where I

take them to the practical you know show them, it links with this and this

and this, try and get them, no grasp yet, I’ve had it now with evolution with

some of the things, then I print out a lot of transparencies, because I still

don’t have my projector going, and then I show them this is where it starts

this is how it works and then hopefully from there we will have some of it

going (smile). But um you know with the resources available you try and

do and do as much as possible. I’ve got piles and piles of National

Geographic’s which I actually page through and show them pictures, I

really try and do a lot (Laugh softly).

325

Researcher: Ok. Have you received any training or attended any course or meeting

where learner misconceptions um or strategies to remedy them have been

discussed?

Teacher 1: Umm, no not since I’ve been teaching. Um I have attended years

ago...separate courses on brain development …um…xxx a lot of those

types of things, I was very young then, but I attended and those are

helping me now I wouldn’t say specifically my teacher training or anything

for that matter, and then I also studied up to Honours in

Psychology…which helps me to understand the children and to

understand, to see in their eyes when they do not understand, to see in

the body language when they do not understand, and I do believe

unfortunately we do not have enough time, I do believe that the naughtier

they are and the more they move about, the less they just do not

understand what you are teaching them, so sometimes I will stop a class

and I will say, you don’t understand the work do you?, then they say no

we don’t, then I say let’s see if we can make a plan and show it to you in a

different way, but I think very often teachers just think they are very

naughty and you know that type of thing, so I would say that my

Psychology training, the fact that I was involved with ..um...a mother who

was ...wat is dit... a counsellor herself, advantaged me, and as far as

training goes with regard to misconceptions, no nothing.

Researcher: Ok, and at subject meetings do you ever get to discuss it there?

Teacher 1: No, at subject meetings we moderate and run away (Laugh)

Researcher: (Laugh) Ok, um. Have you come across any articles on learner’

misconceptions while reading?

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Teacher 1: Yes, I will say if you, if you are the type of person that will specifically go

into that, like ah …there’s very often articles in newspapers like the frontal

develop you know that frontal lobe of teenagers that is not fully developed

yet, their behaviour in class and everywhere in general, towards it, that is

if you are interested to read on that. Yes there is articles in magazines,

there are programmes on DSTV and the internet. If I sometimes have a

child, I will go and read on it, like a child will tell me: “My mother said I

suffer from this.” Then I will actually go and look it up and see how it

affects the child, I doubt if many others do it .…

Researcher: Ok-

Teacher 1: But it’s my interest. I like it. (Smile)

Researcher: Ok, um. In your opinion would practical work and experiments HAVE any

effect on learners’ misconceptions?

Teacher 1: Yes it would, if you had enough time…and enough resources um very

difficult if you work with a class of 35 um…and above …to actually really

ah always do these practical’s because they do get very excited, but I do

believe yes I’ve seen that ..they ah.. you have learners that have such a

poor knowledge on the stuff and if you do a practical …it does help them,

the practical today didn’t help (laugh) but then you should explain very

thoroughly why it didn’t work, but I have seen they ABSOLUTELY LOVE

PRACTICALS and in Technology, ooh they enjoy that, it’s just extremely

noisy, like the problem I had last year is whenever we would hammer

away, because we did not have a specific class for Technology, they run

upstairs from the classes downstairs and they say: “ you are making a

heck of a noise, can you stop!” so there’s a lot of complaints from teachers

around you, when you are busy with practical xx (Laugh) which is a big

problem, if I can have a class in the corner I will just hammer away, so that

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is limiting, but they LOVE to do practical’s, they really do and they

understand the work better and they’re more LESS disruptive.

Researcher: Umm, in this one question that the children did for me, it was a practical,

and the majority of, and they didn’t, and the majority of the kids got the

question right because they had to describe what they SAW, so if they

hadn’t seen it, ok they could have seen it in their textbook but they most

probably wouldn’t remember, but I guessed from the fact that so many

kids got it right that they had seen it, but there were some children that got

it wrong and when I asked them if they had seen it, you know, they said:

“yes, they did the experiment, this was what the experiment was like but

they can’t remember what it looked like.” Why do you think that

sometimes, why do you think it is that sometimes you do the experiment,

the kids do it, they remember doing it, but they can’t remember what they

saw or what the results were or what they were meant to learn, so in fact

sometimes it doesn’t actually help, why do you think that happens

sometimes?

Teacher 1: You know I’ve even done some of those myself um, were... if I think back

when I ... now I’m going to take it to my own…maybe that will help, when I

studied ah..further I didn’t have Science for matric so when I entered the

class like for the third week they did acid and base titrations …now if you

have never seen or you don’t really know what acid and bases is and that

type of thing …they taught us in class and everything was there but when

they did the practical to me it was so foreign …that I was just so

completely lost, and I stood there and I eventually asked the lecturer:

“what exactly are we doing?”, he gave me a terrible answer of: “You

should leave Science, because you will never amount to much”, and up to

this day I remember the class, I remember we did it, but I remember

absolutely NOTHING of what we did. Umm I do think you should have

some knowledge if you do a practical, because otherwise you just, and

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sometimes a learner just ...isn’t there yet, you do, because you now, ok

you say we are going to do this practical today and half the class or three

quarters don’t fully understand exactly what you are doing and you are

explaining to them time and time again, but I must admit there are some

learners that even after you have shown them so many times, they’re still

just not there, they do not understand why you are doing what you’re

doing. I don’t know?

Researcher: Ja, I know it is difficult. Do you think that language would have any effect

on learner misconceptions?

Teacher 1: Yes I do believe that very, yes I do, absolutely...because I have seen in

the past that with learners, I’ve had learners that came in like in grade 8

from schools, rural schools, where they, their English is so limited …and

it’s so difficult to get them to understand what you are doing, no language

definitely…

Researcher: Ok, and the language of Science terminology does that have an effect?

Teacher 1: Yes, yes and your ability to understand that language, ah, and if you are

good with language, if I take Life sciences, if you have a strong language

ability it’s easy to remember all those Latin ... words, and to you know... if

you do not have that ability you can eventually be in matric and you still

battle to spell it and to write it... very specific to children…

Researcher: Ok that all the questions that I have for you. Do you have any questions

for me? (Smile)

Teacher 1: No, I understand why you ask me all these questions, very difficult to put it

into words though, but thank you very nice to once again think, you should

always think on what you are doing.

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O2: Interview with the second teacher – the grade 12 teacher – on 17/08/2009 at

8h30-9h10

Researcher: Question number 1, ok, there are no right or wrong answers obviously, it’s

just your opinion ok, so tell me in your experience with the Science

learners in your class, how common are learner’ misconceptions?

Teacher 2: I think quite common, and it seems to be increasing every year more and

more ja.

Researcher: Ok, why would you say it’s increasing, what do you think it is?

Teacher 2: If I compare my first matric group this is now my second, I think of the

grade 11’s now that are going to matric next year, um, I have to explain

something to the grade 11’s three times, where my first group three years

ago I had to explain it once and they immediately understood. (Pause.)

Researcher: Ok, …, ok, how do you think learners actually develop misconceptions?

Teacher 2: I think it comes from lower grades where they don’t um, they don’t learn

the correct words and what is expected when we say, explain versus

define versus um, state, things like that. I think that is the main issue, they

don’t, they read but they don’t understand what they are reading. Not

necessarily they don’t understand the work, they just don’t know what I

want them to say.

Researcher: Ok, from your point of view what would you say are the main causes of

learner misconceptions?

Teacher 2: (Pause.) The main sources I would think, reading problems, difficulty in

330

reading and understanding, I would say that is the main problem and

then... then secondly I would think mathematical literacy, to be able to

understand Maths, that’s the second thing, so after they have understood

the question, they don’t know how to do the Maths. (I think those are the

main ones.)

Researcher: Um, how would you define a misconception?

Teacher 2: (Pause.) To… to read a question and not to understand it properly and

therefore your answer is incorrect versus the question, it is not necessarily

scientifically incorrect but it is not related to what the question actually

asks.

Researcher: Ok… um what strategies do you use or have you tried, which may remedy

learner’ misconceptions?

Teacher 2: I always try to explain one concept at least in three different ways, and

then I also have, every week at least one extra class, where kids that feel

that they still don’t understand it can come back to me, and then I can

have a one on one talk with them, and I try also to put it in their own words

and in their context of what they understand, cell phones and what they

like, Mix-it and things like that..um and that’s the one way … I try to make

it funny, they remember if you put some humour into it, they remember it

better.

Researcher: Ok… um have you receive any training, or attended any courses or

meetings where learner misconceptions, or strategies for remediating

them, have been discussed?

Teacher 2: No… I have been to courses where the work has been discussed and how

you can do a practical or so, but never misconceptions.

331

Researcher: So at your subject meetings it never really comes up?

Teacher 2: No.

Researcher: And have you marked matric papers?

Teacher 2: Um no I hope this year will be my first.

Researcher: Ok… um … Have you come across any articles on learner’

misconceptions, while reading about Science?

Teacher 2: Also no. (Pause) I know it is a discussed topic in the school at the

moment, that’s why they have this grade 8 program … um where all the

grade 8’s have a little, every register period they write a little, do an activity

or write a little test … to help them to learn certain words, because like it’s

not only a problem in Science, I think it is a overall problem for everybody,

everybody struggles with it, and that’s why they have, they have started

the program this year, from grade 8 to just up their level of language use

and understanding.

Researcher: Which subject do they do it in?

Teacher 2: In the register class, so it’s not a particular subject. In register class they

get a little exercise or a test, but it’s not related to a specific subject.

Broad…

Researcher: Ok… is it a school project

Teacher 2: Yes… they started at the beginning of this year and I hope that we will

have the results at the end of the year, to see whether it helped at all.

332

Because many, many many, teachers complained that they found that

problem, specifically, so that’s why they started this program … and they

have to define certain words and explain, just to try and teach them what

is expected of them when a certain question is asked in a certain way.

Researcher: Ok. … Have you come across any misconceptions in Science textbooks?

Teacher 2: (Pause). Mm ... not that I can put my finger on, but I’m sure that there

would be, there would be I’m sure.

Researcher: Ok. … Um, what are the most common misconceptions that you have

come across in your grade 12 learners’ Physics papers, ones that come

up a lot?

Teacher 2: (Pause). The grade 12’s, let me just look at the topics (looks at textbook).

Um, oh the Physics.

Researcher: Ja.

Teacher 2: (Pause). I know they struggle with force and work and power um ..

electricity a little bit, especially because we only do electromagnetism and

they forget what they have learnt in grade 11 with the circuits and the thing

like that um, they don’t struggle with projectile motion that, they find that

quite easy … what else have we done ..um electromagnetism I would say

is a big one (pause).

Researcher: How do they do with energy?

Teacher 2: Ja that’s the work and power, momentum is ok, they are fine with

momentum and impulse, that they are alright with um but with energy,

work, power they struggle and electromagnetism.

333

Researcher: Ok… um in your opinion would practical work and experiments have any

effect on learner’ misconceptions?

Teacher 2: I think it would, they LOVE doing practical’s, they always want some type

of explosion though, they love doing practical’s, and then they also SEE it,

we don’t only talk about it, they SEE it, and I think the kids are visually

stimulated, they look at things over the TV and they’re visually stimulated,

so seeing it helps, I think it would have a HUGE impact.

Researcher: Sometimes we do experiment, and when we ask them questions later it’s

like as if they have never seen it, why do you think that sometimes it

doesn’t actually work?

Teacher 2: Because I think that um due to the big class ... and expensive equipment,

you can’t always let everybody do his own experiment and so it seems as

if the group is doing well... but I think it’s the clever kids or the kids that

understand more that do most of the work and then you have spectators

which only looks, who doesn’t participate, I think that’s the biggest

problem, if it were possible that everybody does their own experiment it

would be very easy to identify who actually understands what they are

doing and who does not. I think with group work the higher academic

performers, if you can say so, they want to do good, they kind of take over

as leaders,.. and the weaker pupils just look … what they are doing, so

you don’t know if they understand it or not, if you ask them they say: “Yes”

…

Researcher: Ok … do you think language has any effect on learner’ misconceptions?

Teacher 2: (Pause).

334

Researcher: How do you find, what problems do your second language learners have?

Teacher 2: Well at this school all of them, it’s their second or even third language, um

and I really think the English, the English learners understand the words

better, and in Science you get, it’s not the normal English words, (we) talk

about Coulomb and... induction and all these fancy words, so to

understand that on top of maybe a language issue, where they only speak

English at school, but with their friends or at home another language, yes,

they definitely do have a disadvantage.

Researcher: Ok, and do you think that the Science terminology that you spoke about

now, how does that affect learner’ misconceptions, amongst all the

learners?

Teacher 2: After a while if you repeat it many times they get used to it, but … it is

necessary to repeat over and over, the units, the words, etc. I think in

grade 8 and 9, um there’s really not enough emphasis on using the correct

words, and even grade 10 I’m starting to get them used to the words, so

that when they get to grade 11 suddenly they are bombarded with all

these, these words, and they get confused. I think that maybe if we

start using it in grade 8 and 9 and 10 more often, it would help them when

they get to grade 11 and 12, but generally they cope.

Researcher: Ok…

Teacher 2: It is just necessary to repeat it and help them study it.

Researcher: Ok, ok, thank you that’s all, are there any questions that you wanted to

ask?

Teacher 2: Umm…

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Researcher: No questions?

Teacher 2: I would just be interested to find out (how the learners did.)

Researcher: (The researcher then switched off the tape-recorder and then gave the

grade 12 teacher copies of the student’s marked worksheets as well as

sufficient extended memorandums for herself and her students.)

STUDENT MISCONCEPTIONS CELESTÉ VAN NIEKERK …

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