Do you understand each of the graphic organizers on page 4?
Which type do you like best? Physical Science Chapter 12
Slide 4
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
Slide 5
Scientists investigate plan experiments Observe always test the
results 4Physical Science Chapter 1
Slide 6
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
Slide 7
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
Slide 8
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
Slide 9
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
Slide 10
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
Slide 11
qualitative statement: describes something with words
quantitative statement: describes something with numbers or
mathematical equations 10Physical Science Chapter 1
Slide 12
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
Slide 13
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
Slide 14
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
Slide 15
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
Slide 16
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
Slide 17
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
Slide 18
Scientists use standard units of measure that together form the
International System of Units, or SI. 17Physical Science Chapter
1
Slide 19
SI units are used for consistency. SI has seven base units.
derived units: combinations of the base units 18Physical Science
Chapter 1
Slide 20
19Physical Science Chapter 1
Slide 21
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
Slide 22
SI prefixes for small measurements 21Physical Science Chapter
1
Slide 23
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
Slide 24
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
Slide 25
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
Slide 26
Physical Science Chapter 125 Using the conversion factor 1 inch
= 2.54 cm, convert 8.5 inches to cm. Write conversion factor as
fractions
Slide 27
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
Slide 28
Physical Science Chapter 127 Given: 8.5 inches We want inches
to cancel out, so it needs to be in the denominator
Slide 29
Physical Science Chapter 128 Using the conversion factor 1 m =
100 cm, convert 3.2 m to cm. Write conversion factor as
fractions
Slide 30
Physical Science Chapter 129 Given: 3.2 m We want m to cancel
out, so it needs to be in the denominator
Slide 31
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.
Slide 32
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.
Slide 33
Physical Science Chapter 132 Convert 3.2 m to cm
Slide 34
Physical Science Chapter 133 Convert 500 mg to kg
Slide 35
Physical Science Chapter 134 Convert 5 dm to m
Slide 36
Physical Science Chapter 135 Convert 567 cm to mm
Slide 37
Because scientists use written reports and oral presentations
to share their results, organizing and presenting data are
important science skills. 36Physical Science Chapter 1
Slide 38
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
Slide 39
38Physical Science Chapter 1
Slide 40
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
Slide 41
40Physical Science Chapter 1
Slide 42
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
Slide 43
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
Slide 44
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
Slide 45
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
Slide 46
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
Slide 47
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
Slide 48
Write 0.0254 m in scientific notation. Physical Science Chapter
147
Slide 49
Write 6,210 km in scientific notation. Physical Science Chapter
148
Slide 50
Write 2.71 x 10 -9 kg in long form. Physical Science Chapter
149
Slide 51
Write 6.28 x 10 7 m in long form. Physical Science Chapter
150
Slide 52
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
Slide 53
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
Slide 54
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
Slide 55
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
Slide 56
55Physical Science Chapter 1
Slide 57
56Physical Science Chapter 1
Slide 58
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
Slide 59
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
Slide 60
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
Slide 61
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
Slide 62
Perform the following calculation and write the answer with the
correct number of significant figures. Physical Science Chapter
161
Slide 63
Perform the following calculation and write the answer with the
correct number of significant figures. Physical Science Chapter
162