Physical Science Chapter 1 Do you understand each of the graphic organizers on page 4? Which type do you like best? Physical Science Chapter 12.

Physical Science Chapter 1

Do you understand each of the graphic organizers on page 4? Which type do you like best? Physical Science Chapter 12

o Scientists perform experiments to find a new aspect of the natural world explain a known phenomenon check results of other experiments test predictions of current theories 3Physical Science Chapter 1

Scientists investigate plan experiments Observe always test the results 4Physical Science Chapter 1

the knowledge obtained by observing natural events and conditions in order to discover facts and formulate laws or principles that can be verified or tested Physical Science Chapter 15

Most of the time, natural science is divided into biological science, physical science and Earth science. biological science: the science of living things botany, ecology physical science: the science of matter and energy chemistry: the science of matter and its changes physics: the science of forces and energy earth science: the science of the Earth, the atmosphere, and weather geology, meteorology 6Physical Science Chapter 1

pure science: the continuing search for scientific knowledge technology: the application of science for practical purposes Advances in science and technology depend on each other. 7Physical Science Chapter 1

law: a descriptive statement or equation that reliably predicts events under certain conditions theory: a system of ideas that explains many related observations and is supported by a large body of evidence acquired through scientific investigation Theories explain why something happens, laws explain how something works. 8Physical Science Chapter 1

Experimental results support laws and theories. Scientific theories are always being questioned and examined. To be valid, a theory must: explain observations be repeatable be predictable 9Physical Science Chapter 1

qualitative statement: describes something with words quantitative statement: describes something with numbers or mathematical equations 10Physical Science Chapter 1

Models can represent physical events. model: a representation of an object or event that can be studied to understand the real object or event Scientists use conceptual, physical, and computer models to study objects and events. 11Physical Science Chapter 1

1. What are the two branches of physical science? 2. What are three types of models used by scientists? 3. Compare and contrast a scientific law and a scientific theory. Physical Science Chapter 112

Identifying problems, planning experiments, recording observations, and correctly reporting data are some of the most important science skills. Scientists approach a problem by thinking logically. 13Physical Science Chapter 1

Critical thinking helps solve problems logically. critical thinking: the ability and willingness to assess claims critically and to make judgments on the basis of objective and supported reasons 14Physical Science Chapter 1

Scientists use scientific methods to solve problems. scientific method: a series of steps followed to solve problems including collecting data, formulating a hypothesis, testing the hypothesis, and stating conclusions The scientific methods are general description of scientific thinking rather than an exact path for scientists to follow. Physical Science Chapter 115

a possible explanation or answer that can be tested Scientists test a hypothesis by doing a controlled experiment. controlled experiment: an experiment in which the variables that could affect the experiment are kept constant (controlled) except for the one that you want to measure variable: a factor that changes in an experiment in order to test a hypothesis 16Physical Science Chapter 1

Scientists use standard units of measure that together form the International System of Units, or SI. 17Physical Science Chapter 1

SI units are used for consistency. SI has seven base units. derived units: combinations of the base units 18Physical Science Chapter 1

19Physical Science Chapter 1

SI prefixes are for very large and very small measurements. The prefixes are multiples of ten. SI prefixes for large measurements 20Physical Science Chapter 1

SI prefixes for small measurements 21Physical Science Chapter 1

Measurements quantify your observations. length: a measure of the straight-line distance between two points mass: a measure of the amount of matter in an object volume: a measure of the size of a body or region in three-dimensional space weight: a measure of the gravitational force exerted on an object 22Physical Science Chapter 1

1. When might a scientist change a hypothesis? 2. A student needs to measure the volume of a liquid. What tool could the student use? 3. Look at Figure 1 on page 14. Answer the question in the caption. Physical Science Chapter 123

Physical Science Chapter 124 Method that always works: Write conversion factors as fractions that equal 1 Multiply by fractions created Repeat until you get the units you want

Physical Science Chapter 125 Using the conversion factor 1 inch = 2.54 cm, convert 8.5 inches to cm. Write conversion factor as fractions

Physical Science Chapter 126 Conversion factor fractions both equal 1 We can multiply by them without changing the value To decide which fraction to use, look at units of what is being converted

Physical Science Chapter 127 Given: 8.5 inches We want inches to cancel out, so it needs to be in the denominator

Physical Science Chapter 128 Using the conversion factor 1 m = 100 cm, convert 3.2 m to cm. Write conversion factor as fractions

Physical Science Chapter 129 Given: 3.2 m We want m to cancel out, so it needs to be in the denominator

Physical Science Chapter 130 Measurement in SI is based on multiples of 10. To multiply or divide by multiples of 10, you just move the decimal point.

Physical Science Chapter 131 Count the number of columns you move in the table. Move the decimal point the same number of places and in the same direction If converting from a smaller unit to a larger one (like cm to km), move the decimal to the left. (remember to Larger; to Left) If converting from a larger unit to a smaller one (like kg to mg), move the decimal to the right.

Physical Science Chapter 132 Convert 3.2 m to cm

Physical Science Chapter 133 Convert 500 mg to kg

Physical Science Chapter 134 Convert 5 dm to m

Physical Science Chapter 135 Convert 567 cm to mm

Because scientists use written reports and oral presentations to share their results, organizing and presenting data are important science skills. 36Physical Science Chapter 1

Line graphs are best for continuous change. dependent variable: values depend on what happens in the experiment Plotted on the y-axis independent variable: values are set before the experiment takes place Plotted on the x-axis 37Physical Science Chapter 1

Bar graphs compare items. A bar graph is useful for comparing similar data for several individual items or events. A bar graph can make clearer how large or small the differences in individual values are. 39Physical Science Chapter 1

Pie graphs show the parts of a whole. A pie graph is ideal for displaying data that are parts of a whole. Data in a pie chart is presented as a percent. Composition of a Winter Jacket 41Physical Science Chapter 1

To reduce the number of zeros in very big and very small numbers, you can express the values in scientific notation. scientific notation: a method of expressing a quantity as a number multiplied by 10 to the appropriate power 42Physical Science Chapter 1

Some powers of 10 and their decimal equivalents are shown below. 10 3 = 1,000 10 2 = 100 10 1 = 10 10 0 = 1 10 -1 = 0.1 10 -2 = 0.01 10 -3 = 0.001 43Physical Science Chapter 1

Example The adult human heart pumps about 18,000 L of blood each day. Write this value in scientific notation. 1. Move the decimal point until there is one nonzero digit in front of the decimal 1.8000 44Physical Science Chapter 1

2. Count how many places you moved the decimal point and note which direction you moved it. 18000 to 1.8000 moved the decimal 4 places to the left 3. The number of places you moved the decimal gives you the absolute value of the exponent moving 4 places means 1.8 10 4 or 1.8 10 -4 45Physical Science Chapter 1

3. If you move the decimal to the left, the exponent is positive. If you moved it to the right, the exponent is negative 18,000 L can be written as 1.8 10 4 L Hint: Large numbers (more than 10) have positive exponents Small numbers (less than 1) have negative exponents 46Physical Science Chapter 1

Write 0.0254 m in scientific notation. Physical Science Chapter 147

Write 6,210 km in scientific notation. Physical Science Chapter 148

Write 2.71 x 10 -9 kg in long form. Physical Science Chapter 149

Write 6.28 x 10 7 m in long form. Physical Science Chapter 150

When you use scientific notation in calculations, you follow the exponent rules. When you multiply two values in scientific notation, you add the exponents. When you divide, you subtract the exponents. 51Physical Science Chapter 1

Your county plans to buy a rectangular tract of land measuring 5.36 x 10 3 m by 1.38 x 10 4 m to establish a nature preserve. What is the area of this tract in square meters? 1. List the given and unknown values. Given: length (l )= 1.38 10 4 m width (w) = 5.36 10 3 m Unknown: area (A) = ? m 2 52Physical Science Chapter 1

2. Write the equation for area. A = l w 3. Insert the known values into the equation, and solve. A = (1.38 10 4 m) (5.36 10 3 m) Regroup the values and units as follows. A = (1.38 5.36) (10 4 10 3 ) (m m) When multiplying, add the powers of 10. A = (1.38 5.35) (10 4+3 ) (m m) A = 7.3968 10 7 m 2 A = 7.40 10 7 m 2 53Physical Science Chapter 1

accuracy: a description of how close a measurement is to the true value of the quantity measured precision: the exactness of a measurement 54Physical Science Chapter 1

Scientists use significant figures to show the precision of a measured quantity. significant figure: a prescribed decimal place that determines the amount of rounding off to be done based on the precision of the measurement 57Physical Science Chapter 1

Round your answers to the correct significant figures. When you use measurements in calculations, the answer is only as precise as the least precise measurement used in the calculation. The measurement with the fewest significant figures determines the number of significant figures that can be used in the answer. 58Physical Science Chapter 1

Calculate the volume of a room that is 3.125 m high, 4.25 m wide, and 5.75 m long. Write the answer with the correct number of significant figures. 1. List the given and unknown values. Given: length, l = 5.75 m width, w = 4.25 m height, h = 3.125 m Unknown: volume, V = ? m 3 59Physical Science Chapter 1

2. Write the equation for volume. V = l w h 3. Insert the known values into the equation, and solve. V = 5.75 m 4.25 m 3.125 m V = 76.3671875 m 3 The answer should have three significant figures, because the value with the smallest number of significant figures has three significant figures. V = 76.4 m 3 60Physical Science Chapter 1

Perform the following calculation and write the answer with the correct number of significant figures. Physical Science Chapter 161

Perform the following calculation and write the answer with the correct number of significant figures. Physical Science Chapter 162

Physical Science Chapter 1 Do you understand each of the graphic organizers on page 4? Which type do you like best? Physical Science Chapter 12.

Documents

physical science chapter

natural science

ecology physical science

branches of physical

science of matter

biological science

application of science

pure science