1 0 Understanding Physics[1]

8/11/2019 1 0 Understanding Physics[1]

1/20

Physics Module Form 4 Chapter 1 Introduction to physics GCKL 2011

1-1

U N D E R S T A N D I N G P H Y S I C S

Recognise the

concepts ofphysics in

everyday objects

and natural

phenomena

1. Tick () the statements that are related to physics.

Blood circulation in our body is controlled by heart.

A large truck moves faster than a car because it has a more powerful engine.

We need water in our digestion system.

Orange juice is acidic because its taste is sour.

An object on a high building has a large potential energy.

When we heat water, its temperature increased.

We are sweating when our body metabolism is high.

Pure water has pH 7.

We cannot see object in dark

A ship is floating in water.

Human body coordination is controlled by hormone system.Oxidation will act faster in acidic medium.

UNDERSTANDING BASE AND DERIVED QUANTITIES

Recognise

physical quantity

and unit

1. Identify Physical quantities, Magnitude, Unitsand Measuring instrumentfrom the

statements below. Write them into the table below (next page).

AIsmail weigh a wooden block that has mass of 500 gram using a lever beam balance.

B Ong Beng Hock measures the length of a building which is 100 meter long using ameasuring tape.

C Siew Mei measures her bodys temperature using a digital thermometer and obtains

38C.

D Bathumalai determines the volume of water using a measuring cylinder and obtains150 milliliter.

E Hanisah measures the diameter of a wire which is 1.26 millimeter using a

micrometer screw gauge.

F Vinisha takes the time of 20 oscillations of a pendulum using a stopwatch andobtains 24.6 seconds.

Statement Physical quantity Magnitude UnitMeasuring

instrument

A

B

C

D

E

F

1.1

1.2


2/20


1-2

Define base

quantities and

derived quantities

are

2. Identify base quantities and derived quantity from the equation below.

(a) Volume = length x length x length

Base quantity = (i) _________________

Derived quantity = (i) _________________

(b) Area = length x length

Base quantity = (i) _________________


(c)

Base quantity = (i) _________________ (ii) ____________________


(i) Base quantity is physical quantity that __________ be derived from any quantities.

(ii)Derived quantity is physical quantity that ___________________ from the basequantities.

List base quantitiesand their S.I unit

3. Choose base quantities from the physical quantities given above and state their S.Iunits.

No. Base Quantity S.I Unit

1.

2.

3.

4.

5.

PHYSICAL QUANTITY

Pressure Time Current

Length Area Temperature

Weight Force Volume

Work Energy Power

Velocity Mass

S.I UNIT

Second Newton Ampere

Kelvin kilogram Pascal

Joule m2 Watt

m s-1

meter m3


3/20


1-3

List some derived

quantities and their

S.I units

4. Write 5derived quantities from physical quantities given in the box above (previouspage) and state their S.I units.

No. Derived Quantity S.I Unit

1.

2.

3.

4.

5.

Express quantities

using scientific

notation

5. Rewrite the values below in scientific notation (Standard notation)

No. Original value Scientific notation

1. 12 000 m

2. 3 000 000 000 s3. 0.000 000 000 56 N

4. 0.000 78 J

5. 0.0034 A

Express quantities

using prefixes

6. Arrange the prefixes given below in ascending order. Then, state their multiple / sub-multiple.

No. PrefixMultiple /

Sub-multipleNo. Prefix

Multiple /

Sub-multiple

1. 7.

2. 8.

3. 9.

4. 10.

5. 11.

6. 12.

Solving problem

involving

conversion of units

1. Rewrite the values below using the suitable prefix.

(i) 4.1 x 1012

m = __________ (vii) 3.8 x 102K = __________

(ii) 9.3 x 101s = __________ (viii) 1.7 x 10

9W = __________

(iii) 0.5 x 10-3

J = __________ (ix) 4.1 x 103C = __________

(iv) 11.2 x 10-2

N = __________ (x) 9.5 x 10-6

A = __________

(v) 5.9 x 106V = __________ (xi) 8.6 x 10-12m = __________

(vi) 6.6 x 10-9m = __________ (xii) 2.2 x 10-1s = __________

PREFIXES

Nano (n) kilo (k) pico (p)

mega (M) centi (c) giga (G)

deci (d) deca (da) tera (T)hector (h) micro () milli (m)

MULTIPLE / SUB-MULTIPLE

103

109 10

-2

101

10-12

106

10

-6

10

2

10

-1

10

-9 10

-3 10

12


4/20


1-4

2. Replaced the prefix in the values below with the correct multiple or sub-multiple.

(i) 4.1Tm = __________ (vii) 3.8 daK = __________

(ii) 9.3 ms = __________ (viii) 1.7 GW = __________

(iii) 0.5 kJ = __________ (ix)4.1 hC

= __________

(iv) 11.2 cN = __________ (x) 9.5 A = __________

(v) 5.9 MV = __________ (xi) 8.6 pm = __________

(vi) 6.6 dm = __________ (xii) 2.2 ns = __________

Check Yourself 1

1.

2.

3.

4.

5.

6.

7.

8.

9.

Which physical quantity has the correct S.Iunit?

Physical quantity S.I unit

A Temperature CelciusB Time minuteC Mass NewtonD Length metre

Time, speed, density, and energy are ..............quantities.

A base C vectorB scalar D derived

Which of the following shows the correct

relationship between the base quantities fordensity?

A

B

C

D

Which of the following is nota base S.I unit?

A Gram C AmpereB Kelvin D Meter

Which of the following physical quantities isnota base quantity?

A Weight C TemperatureB Time D Electric current

A radio station airs its programmes bytransmitting waves at a frequency of

102.3 MHz. How much is this frequency, inHz?

A 1.023 x 102

B 1.023 x 10

5

C 1.023 x 106

D 1.023 x 108

Which of the following values is equal to 470pF?

A 4.7 x 10-10

FB 4.7 x 10

11F

C 4.7 x 10-7

FD 4.7 x 10

2F

Hamid cycles at a velocity of 3.1 km h-

.What is this velocity, in m s-1?

A 0.09 C 1.16B 0.86 D 11.61

Which measurement is the longest?

A 2.68 x 103m

B 2.68 x 10-1

mmC 2.68 x 103cmD 2.68 x 10

-4m


5/20


1-5

1.

10. 11.

UNDERSTANDING SCALAR AND VECTOR QUANTITIES

Define scalar and

vector quantities.1. Read the statements below to make a generalisation on scalar quantity and vector

quantity. Then classify the physical quantities into scalar quantity and vector quantity

in the table below.

AHasan walks with a velocity of 2 m s-1due West.

B Husna runs with a speed of 5 m s-1

.

C Sangeetha walks along a displacement of 40 m dueNorth.

D Jason runs along a distance of 30 m.

E Chin Wen push the table downwardswith a force of 30 N.

F Wen Dee has a mass of 40 kg.

Scalar Quantity Vector Quantity

(i) Scalar quantity is physical quantity that has _______________________.

(ii) Vector quantity is physical quantity that has _______________________ and

________________________.

Differentiate

between distance

and displacement.

2. Underlinethe correct physical quantity.

(i) (Distance / Displacement) is the total lengthtravelled by an object.

(ii) (Distance / Displacement) is the shortest length measured between the initial

point and the final point.

Which of the following conversion of unit iscorrect?

A 24 mm3 = 2.4 x 10

-6m

3

B 300 mm3 = 3.0 x 10

-7m

3

C 800 mm3 = 8.0 x 10-2m3

D 1 000 mm3 = 1.0 x 10-4m3

Which of the following frequencies is thesame as 106.8 MHz?

A 1.068 x 10-4HzB 1.068 x 10

-1Hz

C 1.068 x 102HzD 1.068 x 106HzE 1.068 x 10

8Hz


6/20


1-6

EXAMPLE:

Check Yourself 2

1.

2.

3.

4.

A B

C

4 m

3 m

A boy walks from A to C through B.

(i) Distance of the boy = 4 m + 3 m = 7 m

(ii) Displacement of the boy = = 5 m

Diagram below shows the path travelled by a

car from P to S.

What is the displacement of the car?

A 5.0 km C 8.2 km

B 6.8 km D 9.0 km

Which quantity is a vector quantity?

A Area C DistanceB Length D Displacement

Which of the following is group of vectorquantities?

A Velocity, mass, displacement

B Speed, time, accelerationC Force, velocity, displacementD Area, temperature, momentum

Which of the following quantities is a vectorquantity?

A Energy C ForceB Power D Pressure

5 km

3 km

1 km

P Q

S R


7/20


1-7

U N D E R S T A N D I N G M E A S U R E M E N T S

Recognise

appropriate

instrument for

physical quantities

1. State the suitable measuring instrument for the physical quantities in the table below.

No. Physical Quantity Measuring Instrument

1. Temperature

2. Length

3. Time

4. Mass

5. Electric current

6. Voltage

7. Density

8. Atmospheric pressure

9. Pressure

10. Force

11. Volume

12. Diameter of tube

13. Diameter of wire

Measure physical

quantity using

vernier calliper.

2. Label the part of vernier calliperbelow.

MEASURING INSTRUMENT

Metre rule Barometer Thermometer Lever balance

Spring balance Hydrometer Measuring cylinder Bourdon gauge

Ammeter Voltmeter Stopwatch Vernier calliper

Micrometer screw gauge

PART OF VERNIER CALLIPER

Inner jaws Outer jaws Main scale Vernier scale

1.4

0 1 2 3 4 5 6


8/20


1-8

3. Take the reading from a vernier calliper:

EXAMPLE:

4. Read the vernier calliper below.

(i) (ii)

(ii) (iv)

Measure physical

quantity using

micrometer screwgauge.

5. Label the part of micrometer screw gaugebelow.

(i)

Read the main scale.

Main scale reading = 0.70 cm

(ii)Read the vernier scale.

Vernier scale reading = 0.02 cm

(iii)Total up the readings.

Actual reading = 0.72 cm

3 4

0

Main scale = ....................

Vernier scale = ....................

Actual reading = ....................

2 3

0

Main scale = ....................

Vernier scale = ....................

Actual reading = ....................

8 9

0

Main scale = ....................

Vernier scale = ....................

Actual reading = ....................

0 1

Main scale = ....................

Vernier scale = ....................

Actual reading = ....................

PART OF MICROMETER SCREW GAUGE

Anvil Spindle Sleeve Thimble Ratchet

0 1 2

0

(i)

0.70

(ii)0.02


9/20


1-9

6. Take the reading from a micrometer screw gauge.

EXAMPLE:

7. Read the micrometer screw gauge below:

(i) (ii)

(iii) (iv)

(i) Read the sleeve scale (main scale).

Sleeve scale reading = 3.00 mm

(ii) Read the thimble scale.

Thimble scale reading = 0.44 mm

(iii)Total up the readings.

Actual reading = 3.44 mm

0 50

40

(i)

3.00 mm

(ii)0.44 mm

0 30

20

Sleeve scale = ....................

Thimble scale = ....................

Actual reading = ....................

020

10

Sleeve scale = ....................

Thimble scale = ....................

Actual reading = ....................

0

20

10

Sleeve scale = ....................

Thimble scale = ....................

Actual reading = ....................

060

50

Sleeve scale = ....................

Thimble scale = ....................

Actual reading = ....................


10/20


1-10

Explain sensitivity. 8. Table below shows readings from three instruments J, K, and L that are used inmeasuring the mass of a Petri dish.

Instrument J Instrument K Instrument L

20 g 19.4 g 19.42 g

A piece of dried leaf of mass 0.05 g is then put in the Petri dish.

(i) Which instrument is able to detect the small change of the mass? [...............]

(ii) Which instrument is the most sensitive? [................]

(iii) Which instrument has the highest sensitivity? [................]

(iv) Sensitivity of instrument is the capability of the instrument to ...............................

..................................................................................................................................

(v)

Which instrument gives reading in the most decimal place? [.................](vi) The ...................... the decimal place, the ........................... sensitivity of the

instrument.

Explain accuracy. 9. Table below shows readings from three instruments P, Q, and R that are used in

measuring the length of a wire. The actual length of the wire is 10.0 cm.

Instrument P Instrument Q Instrument R

10.1 cm 10.4 cm 9.6 cm

(i) Which instrument gives the closest reading to the actual length of the wire?

[...............]

(ii) Which instrument gives the most accurate reading? [...............]

(iii) Which instrument has the highest accuracy? [...............]

(iv) Accuracy of instrument is the capability of the instrument to ..................................

...................................................................................................................................

Explain

consistency

(Precision)

10.Table below shows four readings from three instruments X, Y, and Z that are used inmeasuring the length of a wire. Each instrument repeats the measurement for fourtimes.

Instrument X 10.0 cm 10.1 cm 10.1 cm 10.0 cm

Instrument Y 10.1 cm 10.4 cm 10.2 cm 9.8 cm

Instrument Z 9.8 cm 9.6 cm 9.9 cm 9.5cm

(i) Which instrument gives readings with the smallest deviation (difference)?

[...............]

(ii) Which instrument gives the most consistence readings? [...............]

(iii) Which instrument has the highest consistency? [...............]

(iv)

Consistency of instrument is the capability of the instrument to .............................

...................................................................................................................................


11/20


1-11

Explain type of

experimental error.

11.In an experiment, the readings of measurement taken may have slightly difference due

to some mistakes. The difference in the readings is called as .........................................

12.These errors can be caused by the change of environment, human factors or the

deficiency of measuring instrument.

13.Error that is caused by environment and human usually is (constant / changeable)*.

14.Error that is caused by the instrument is always (constant / changeable)*.

15.Type of Error:

Random Error Difference Systematic Error

Cause

Magnitude /

value

Example

Method toreduce the

error

Check Yourself 3

1. 2..

A, B, C, and D shows the shooting marks on atarget. Which marks can explain the conceptof precision of a measurement?

A C

B D

A, B, C, and D show parts of four differentbalance scales. Which balance is the mostsensitive?

A C

B D


12/20


1-12

3. 7.

4.

8.

5.

9.

6.

Diagram below shows the target board in agame.

Which result is consistent but notaccurate?

A C

B D

The diagram shows the scale of a micrometerscrew gauge.

What is the reading of the micrometer?

A 7.02 mm C 7.03 mmB 7.52 mm D 7.58 mm

TargetTarget

board

The diagram shows the scale of a verniercalliper.

What is the reading of the vernier calliper?

A 2.16 cm C 1.86 cmB 2.06 cm D 1.76 cm

Atmospheric pressure can be measured byusing

A hydrometer

B Bourdon gauge and manometerC Bourdon gauge and mercury barometerD manometer and mercury barometer

Table below shows the readings of thethickness of a board which are taken by fourstudents.

StudentReading/cm

1 2 3 4

A 2.50 2.50 2.50 2.50B 2.53 2.53 2.53 2.53

C 2.52 2.53 2.54 2.53

D 2.71 2.73 2.74 2.74

Each student made four measurements. If the

actual thickness of the board is 2.53 cm,which of the students A, B, C, and D madethe measurements that are accurate but notconsistent?

Diagram (a) shows the reading of a verniercalliper while its jaws are closed. Diagram (b)shows the reading of the vernier calliper whena metal sheet is placed between the jaws.

What is the thickness of the metal sheet?A 0.46 cm C 0.38 cmB 0.42 cm D 0.32 cm

(b)(a)

The diagrams show the scales on a pair ofvernier callipers and a metre rule.

Which comparison is correct about thesensitivity of the vernier callipers and themetre rule when measuring the thickness of awire?

Vernier callipers Metre rule

A Low sensitivity Low SensitivityB Low sensitivity High sensitivityC High sensitivity Low sensitivityD High sensitivity High sensitivity

Vernier calliper Metre rule


13/20


1-13

10. 14.

15.

11.

12.

13.

Four students, A, B, C, and D use a micrometerscrew gauge, a metre rule, and a verniercalliper to measure the thickness of a board.Which student records the reading correctly?

Micrometer Metre Vernier

screw rule/mm calliper/mmgauge/mm

A 11.1 11 11.13B 11.13 11.1 11.128C 11.128 11.1 11.13D 11.13 11 11.1

The diagram shows the scale of a micrometerscrew gauge.

What is the reading of the micrometer?

A 4.95 mm C 4.50 mmB 4.55 mm D 4.45 mm

Which of the following statements is correctaboutzero error?

A Can be reduced by determining averagereading.

B The magnitude of error increases when

the value of the reading increases.C Exist either in positive or negative.D The magnitude of error increases if the

range of scale is large.

Which of the following ways can reduce theparallax error while taking reading of currentfrom an ammeter?

A Use a higher sensitivity ammeter.B Repeat the measurement and calculate

the average reading.C Take the reading using a magnifying

glass.D Use ammeter that has plane mirror

below the pointer.

What is the function of the plane mirror underthe pointer in an ammeter?

A To increase the consistency of themeasurement.

B To increase the accuracy of themeasurement.

C To avoid parallax error.D To prevent zero error.

Diagram below shows two types of ammeters,X and Y, that can be used to measure electriccurrent.

(a) Which ammeter is more sensitive?

...................................................................

(b) State one reason for your answer above.

...................................................................

...................................................................

...................................................................


14/20


1-14

16.

18.

17.

Figure below shows the scale of an ammeter.

(a)Name the physical quantity measured bythe ammeter.

...................................................................

(b)

What is the value of the smallest divisionon the scale?

...................................................................

(c) State the function of the mirror locatedunder the scale.

...................................................................

...................................................................

Mirror

Figure below shows a vernier calliper used tomeasure external diameter of a hollow

cylinder.

(b)Name the part labelled X.

...................................................................

(c) What is the function of X?

...................................................................

...................................................................

(a) The external diameters of the cylinder atfour different places are shown in thetable below.

External diameter/cmRelative

deviation/%

2.04 2.05 2.04 2.06 0.37

(i) Why is the external diameter

measured four times?

.............................................................

.............................................................

(ii)What is the purpose of calculating therelative deviation?

.............................................................

.............................................................

.............................................................

Figure below shows the meniscus of oil in ameasuring cylinder. P, Q and R are three eyepositions while measuring the volume of the

oil.

(a) Which position of the eye is correct while

taking the reading of the volume of oil?

...................................................................

(b) Give one reason for the answer above.

...................................................................

...................................................................


15/20


1-15

19.

U N D E R S T A N D I N G S C I E N T I F I C I N V E S T I G A T I O N

Identify variables

in a given situation1. Identify and state the variables that can be investigated from the situations below.

EXAMPLE:The car moves faster when it is pushed harder.

Cause : pushed harder Manipulated variable : Force

Effect : moves faster Responding variable : Speed/Velocity/Acceleration

No. SituationManipulated

variable

Responding

variable

1. The temperature of smaller block risesfaster when it is heated.

2. The pendulum system with longer stringtakes longer time to stop.

3. The loaded lorry is harder to stop than theempty lorry.

4. The trolley that falls from the higher place

moves faster.

5. The spring becomes longer when it ispulled harder.

A student is assigned to measure the thicknessof a metal sheet. The student is provided witha vernier calliper.

(a) The student uses the vernier calliper tomeasure the thickness of the metal sheet.

Figure (i) shows the scale of the verniercalliper while the jaws are closed. Figure(ii) shows the scale of the vernier calliperwhen the metal sheet is put between thejaws.

(ii)

(i)

(i) What is the zero error of the verniercalliper?

.............................................................

(ii) Calculate the thickness of the metal

sheet.

Thickness = .................................

1.5


16/20


1-16

Making inference 2. Write inference from the given variables.

EXAMPLE:

Manipulated variable : Length Responding variable: Time

Inference: The length affects the time taken.

No.Manipulated

variable

Responding

variableInference

1. Force Acceleration

2. Mass Temperature

3. Force Extension

4. Mass Time

5. Force Pressure

6. Area Pressure

7. Temperature Volume

Form hypothesis. 3. Write hypothesis from the given variables.

EXAMPLE:

Manipulated variable : Length Responding variable: Time

Hypothesis: The longerthe length, the longerthe time taken.

No.Manipulated

variable

Responding

variableHypothesis

1. Force Acceleration

2. Mass Temperature

3. Force Extension

4. Mass Time

5. Force Pressure

6. Area Pressure

7. Temperature Volume


17/20


1-17

Analyse the data. 4. Data obtained from an experiment can be analysed by plotting a line graph.

Manipulated variable is on the x-axis, and responding variable is on the y-axis.

The variables must be stated together with the correct unit.

EXAMPLE:

Manipulated variable : Mass

Responding variable : Time

5. Sketch a graph to analyse the following variables:

(i) Manipulated variable : Force (ii) anipulated variable : Mass

Responding variable : Accelerationesponding variable :

Temperature

(iii) Manipulated variable : Force (iv) Manipulated variable : Mass

Responding variable : Extension Responding variable : Time

Mass/kg

Time/min


18/20


1-18

(v) Manipulated variable : Force (vi) Manipulated variable : Area

Responding variable : Pressure Responding variable : Pressure

Interpret data to

draw a conclusion.

6. The conclusion of an experiment is made based on the line graph obtained.

EXAMPLE:

Conclusion: Conclusion:

The time is directly proportionalto the mass.

The pressure is inversely proportionalto the area.

Conclusion:

The temperature is linearlyincreasingwith the time.

Mass/kg

Time/min

Pressure/Pa

m-2

Time/min

Temperature/C


19/20


1-19

Interpret data to

draw a conclusion.

7. Write a conclusion based on the line graphs below:

(i) (ii)


........................................................

........................................................

.......................................................

.............................................................

.............................................................

.............................................................

(iii) (iv)


........................................................

........................................................

.......................................................

.............................................................

.............................................................

.............................................................

Length/cm

Period /s Temperature/C

kg-

Pressure/kPa Force/N

Volume/m3

Extension/cm


20/20


1-20

A

C

B

D

Check Yourself 4

1.

.

4.

2.

5.

3.

Which of the following graphs obeys theequation F = kx, where k is a constant?

A C

B D

Table below shows the results of an experimentto investigate between load and extension whena spring is stretched.

Load, F/N 100 150 200 250 300

Extension,

x/cm1.0 1.5 2.0 2.5 3.0

The original length of the spring is l0= 15.0 cm.What is the manipulated variable?

A Load, FB Extension, xC Original length of the spring, l0D Material used to make the spring

The graph shows the relationship between vand t.

The relationship between v and t is

represented by the equation

Diagram below shows an investigation aboutthe stretching of a spring. Babies of differentmasses are supported by identical springs.

Which of the following variables are correct?

Manipulated

variable

Responding

variable

Constant

variable

A Mass of thebaby

Length ofthe spring

Diameter ofthe spring

B Length ofthe spring

Mass of thebaby


C Diameter of

the spring

Length of

the spring

Mass of the

baby

D Mass of thebaby


Length ofthe spring

The graph shows the relationship betweenphysical quantitiesPand Q.

Which statements about the graph is correct?

A If Q= 1, thenP= 2.

B The gradient of the graph is 1.C Pis directly proportional to Q.D The equation of the graph isP= 1 + 3Q

1 0 Understanding Physics[1]

Documents