Updated 10/08/07
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1.1 What is Physics
Section 1.1 Review Q, pg 9:
1] Mechanics, thermodynamics, vibrations and wave phenomena, optics,
electromagnetism, relativity, and quantum mechanics.
2a] mechanics; because the ball is a moving, spinning object.
b] Thermodynamics; because cooking concerns changes in temperature.
c] vibrations and wave phenomena; because music is a type of sound.
d] Electromagnetism; because lightning is a form of electricity.
e] Optics; because the lenses decrease the light intensity that
reaches your eye.
3] Observing and collecting data, formulating and testing hypotheses,
interpreting results and revising the hypothesis, stating conclusions.
4] Physicists model the physical world through diagrams, equations, and computer
simulations.
5a] mechanics [b] thermodynamics [c] electromagnetism
Ch 1 Review Q, pg 27
1a] vibrations and wave phenomena, electromagnetism
b] mechanics, vibrations and waves
c] optics, thermodynamics
d] thermodynamics, mechanics.
2] Approaches a & d fit the scientific method.
3] Collect information on different cars, hypothesize about which car best suits
your needs, test your hypothesis with test drives, interpret the results of your
test drives, rethink your needs, and choose the best car to buy.
4] The facts that the fox is brown and the dog is lazy will be ignored.
1.2 Measurements in Experiments
Practice A, Metric Prefixes, pg 15
[1] 5x10-5 m [2] 1x10-6
s
[3a] 1x10-8 m [b] 1x10-5
mm [c] 1x10-2 μm
[4] 0.15 Tm, 1.5x108 km [5] 1.440x103
kg
Section 1.2 Review Q, pg 20:
[1a] meters [b] kilograms [c] seconds
[2a] 6.20x10-6 kg [b] 3x10-6
ms [c] 8.80x104 m
[3a] 0.67 [b] 14 [c] 778.92 [d] 797.5
[4a] accurate and precise [b] precise [c] neither
Ch 1 Review Q, pg 28:
5a] s or das [b] kg or Mg [c] m [d] cm or dm [e] g or dag
f] Ms [g] km [h] kg [i] m or dam [j] cm, dm or m
6] m2/s2
7] kg/s
8] The size of the unit varied depending on who was doing the measuring.
9] The size of the unit is standardized and reproducible.
10] kg●m2/s2
11a] 200 mm [b] 7800 s [c] 1.6x107
μg d] 7.5x104 cm
e] 6.75x10-4 g [f] 4.62x10-2
cm [g] 9.7 m/s
[12a] 1 dekaration [b] 2 kilomockingbirds [c] 1 microphone
[d] 1 nanogoat [e] 1 examiner
[13] 1.08x109 km
[14] 11 people
1.3 The Language of Physics
Section 1.3 Review Q, pg 25:
[1] units: a, e. variables/quantities: b, c, d, f
[2a] kg●m/s2 [b] kg●m/s3
[c] kg●m2/s3
[d] kg●m/s2
[3] d [4] a [5] c
Ch 1 Review Q, pg 28: Accuracy, Precision, &
Significant Figures
15] Yes, as set of measurements could be precise (have a high number of
significant figures) but not close to the true value due to an error with the
measuring instrument.
16a] 1 [b] 3 [c] 5 [d] 4 [e] 4 [f] 6
17] No, the number of significant figures is not consistent
between the two values in each example
18a] 3.00x108 m/s [b] 2.9979x108
m/s [c] 2.997x103 m/s
19a] 3 [b] 4 [c] 3 [d] 2
20a] 797 g [b] 0.90 m/s [c] 17.8 mm [d] 23.7 s
21] 228.8 cm
22] 115.9 m
Dimensional Analysis & Order-of-Magnitude Estimates, pg 29
23] b, c
24a] 10-2 m [b] 100
m [c] 101 to 102
m [d] 101 m [e] 102
m
25] No, dimensional consistency indicates that the equation may be valid,
but is not necessarily valid.
26] The dimensions are consistent.
27] The dimensions are consistent.
28] The equation is not valid.
29] ~4x108 breaths. 33]
~2000 balls
30] ~9x104 beats. 34]
~1x1010 lb, 2 x107
cattle
31] ~5.4x108 s. 35]
~700 tuners
32] ~4x107 revolutions. 36]
~8x105 balls
Ch 1 Mixed Review, pg 30
[37a] 22 cm; 38 cm2
[b] 29.2 cm; 67.9 cm2
[38] Take the $5000 because it would take you 272 years to count out the $5
billion in single dollar bills.
[39] 9.818x10-2 m
[40] 1.79x10-9 m
[41] The ark (6x104 m3)
was about 100 times as large as a typical house (6x102
m3)
[42] 3.2x1010 years
[43] 1.0x103 kg
[44a] 5x10-16 kg [b] 1x10-5
kg
[45] 0.618 gm/cm3 [b] 4.57x1016
m2
Ch 1 Standardized Test Prep, pg 32
[1] B [2] J [3] A [4] H [5] C [6] G [7]
C [8] J [9] B
[10] F [11] C [12] F [13a] 2 [b] 3 [c] 3 [d] 4
[14] 26 897 m [15] time
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1 What are the 3 big ideas of science?
a] The scientific method is used to discover broad principles that can be
used to predict the behavior of objects & systems.
b] Careful measurement is an important part of describing the behaviors of
objects and systems.
c] Displaying data in tables and graphs makes it easier to see patterns and
discover relationships.
Objective: Identify activities and fields that involve
the major areas within physics.
2 Relate the parts of a car to physics.
See Fig 1, pg 4
Mechanics (Ch 2-7): Drive Train: Engine, transmission, wheels
Vibrations & Waves (Ch 11-12): Shock absorbers, engine, breaks,
tires, & radio speakers
Thermodynamics (Ch 10): Engine, air conditioner
Optics (Ch 13-15): Lights & mirrors
Electromagnetism (Ch 16-20): Battery, starter, generator, lights.
Quantum Mechanics (Ch 21 & 22): none
3 a] Biology includes respiration, digestion, growth,
reproduction, etc. What science forms the basis of biology?
Chemistry
4 In Chemistry you studied atoms, molecules, gases.
a] What holds atoms & molecules together?
Electrostatic forces (Ch 4)
b] What causes pressure?
Molecular collisions with container walls. (Ch 6)
c] Why is heat absorbed or released in a chemical reaction?
Heat is absorbed to break the chemical bonds and released when new
ones form. (Ch 5, 9, 10)
d] What science forms the basis of chemistry?
Physics
Objective: Describe the processes of the scientific
method.
5 Draw and label the scientific method.
a]
Make observations and
collect data that lead to a question
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b] Formulate and test hypotheses by experiments.
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c] Interpret Results |
State Conclusions |
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d] Hypothesis ------Contradicted----->-+
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Confirmed
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e] Law after others also confirm it.
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f] Formulate a Theory
Objective: Describe the
role of models and diagrams in physics.
6 a] What is a model?
A model is a simplified representation designed to show how a system or
object works.
b] Describe four types of models.
i] PHYSICAL--DAMS, SHIPS, PLANES, & BUILDINGS
ii] MATHEMATICAL--PROCEDURES (TAXES), EQUATIONS
iii] LOGICAL--CAUSE & EFFECT RELATIONSHIPS--THE SUN RISES & SETS
BECAUSE THE EARTH ROTATES ON ITS AXIS;
iv] SIMULATORS: PLANETARIUMS, FLIGHT SIMULATORS, VIRTUAL REALITY
c] State Newton’s Law of Ratios.
"A MODEL WILL PREDICT THE BEHAVIOR OF AN OBJECT WITH ALL THE SAME RELEVANT
RATIOS."
d] Give an example of Newton’s Law of Ratios.
A PLASTIC AIRPLANE MODEL WILL PREDICT THE BEHAVIOR OF A SIMILAR OBJECT (NO
ENGINE). AT MINIMUM, IT IS LACKING THE POWER/WEIGHT RATIO AND THE WEIGHT/WING
AREA RATIO.
e] What role do models in physics play?
Models are used to
1] explain the basic features of a phenomena
2] predict outcomes when a variable changes.
Objective: Differentiate
between laws, theories, and hypotheses.
7 a] What
is a hypothesis?
An educated guess in the form of “If X then Y.”
b] Give an example of a hypothesis?
If you double the temperature the reaction speed will double.
c] What is a law?
A cause and effect relationship, without an explanation.
d] Give an example of a law.
Ex#1: Force of Gravity = a attractive force between any two objects.
Fg = GxMass 1 x Mass 2 .
(Distance between centers of gravity)2
e] How does a hypothesis become a law?
If, after many tests, no one can demonstrate the hypothesis incorrect it
is accepted as a law.
f] Name a law, state it, and state how it was proven incorrect.
#1: Caloric theory explained how things became hotter and cooler.
Caloric was a fluid that flowed from hot things to cool. It could not explain
why rubbing two rough surfaces together made them warmer. Kinetic theory said
that heat is a form of energy that is transferred when fast-moving particles hit
other.
#2--The law of gravity once was: "What goes up must come down."
Newton developed a theory that predicted the measured orbits of the planets
which are up and don't come down. His law is: Fg = GM1M2/d2
#3: The Law of Conservation of Mass & Energy once was: "Matter and energy
cannot be created or destroyed." They investigated nuclear reactions and found
the E = mc2, or the energy created in a nuclear reaction = the mass
destroyed x speed of light squared.
g] Define a theory.
a tested set of statements that explains and predicts an outcome.
h] State an example of a theory.
Ex#1: Spontaneous Generation: certain forms of life (flies, worms, mice)
can spontaneously grow out of non-living things such as mud or decaying flesh.
Ex#2: Darwin’s theory of evolution. Creatures that adapt to changes in their
environment will have better chances of survival, and be less likely to become
extinct, than those who don’t.
Ex#3: The Kinetic Theory of Heat explains how heat moves from a hot to cold
object & not the reverse, and why rubbing two things together produces heat.
i] Explain how a hypothesis can become a theory.
A hypothesis cannot become a theory for it has no explanation.
Objective: Describe the
role of models in physics.
9 a] What is a model?
b] Describe four types of models.
c] State Newton’s Law of Ratios.
d] Give an example of Newton’s Law of Ratios.
e] What role do models in physics play?
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Objective: List basic SI units and the quantities they
describe
1 a] Define and state an example
of a fundamental concept.
Fundamental concept is the simplest type of concept.
Ex: distance, time, mass
b] Define and state an example of a derived concept.
Derived concepts are 2 or more fundamental concepts combined.
Ex: Speed = distance/time, Area = distance x distance
2 Fill in the following table (turn paper sideways):
F| Concept | Equation | English | Metric | Instrument
N|----------------------------------------------------------------
D| Distance |----------| foot | meter | ruler
M| Time |----------| second | second | clock
T| Mass |----------| slug | kilogram| balance
L| Temperature |----------| Fahrenheit | Celsius | thermometer
-----------------------------------------------------------------
D| Area | A = LxW | ft2 | m2 |
Ruler
R| Volume | V = LxWxH| ft3 | m3 |
Ruler
V| Density | D = M/V | Slug/ft3 | kg/m3 |
Balance & Ruler
D| Speed | S = D/t | ft/s | m/s | Ruler & Clock
Objective: Apply
dimensional analysis to calculations.
3 What two dimensions, in
addition to mass, are commonly used by physicists to derive additional
measurements?
3 7 km
* 60 min * 60 s = 25,200(?)
h h min
Obj:
Distinguish between accuracy and precision.
5 a]
Accuracy indicates how close to the accepted value measurement is.
Ex: A physics test is not an accurate measure of intelligence.
b] Precision indicates how reproducible your measurement is.
It is the smallest division on a scale.
It describes the limitations of the measuring instrument.
Ex: A meter stick has a precision of 1 mm or 1/1000 m
6 Error in
experiments must me minimized to obtain accurate predictions.
Method error (using two different methods to measure the same thing) can be
minimized by standardizing the measuring measurements.
Instrument error (due to faulty instruments, ex a balance not zeroed) can be
minimized by keeping instruments in good working order.
Obj: Use
significant figures in measurements and calculations.
7
Significant figure is a digit read on an instrument.
When reading an instrument, do not round off, report all digits.
Ex: a reading of 25 cm on a meter stick should be reported as
25.0 cm, because meter sticks are accurate to 0.1 cm
When multiplying and dividing the basic rule is:
The smallest number of sig. fig in = the sig fig out.
When adding and subtracting the rule is:
The smallest number of decimals in = number of decimals out.
Obj: Convert measurements into scientific notation.
Practice A
SI Prefix Table: n = nano = 10-9: 1 nm =
10-9 m or 109 nm = 1 m
1 D = 50 μm x _?_ = _?_m
See SI Prefix table inside back cover.
50 μm x 10-6 m = 50 x 10-6 m
μm
2 T = 1 μs x _?_ = _?_s
T = 1 μs x 10-6 s = 1 x 10-6
s
s
3 a] 10 nm x _?_ = _?_m
10 nm x 10-9 m = 10-8 m
nm
b] 10 nm x _?_ = _?_mm
Note: 1 mm = 10-3 m = 1/1000 m or 1000 mm = 1 m
10 nm x 10-9 m x 1000 mm = 10-5
mm
nm m
c] 10 nm x _?_ = _?_μm
Note: 1 nm = 10-9 m = 1/10-9 m or 109 mm = 1 m
10 nm x 10-9 m x 106 μm
= 10-2 μm
nm m
4 1.5x1011m x _?_ = _?_ km
1.5x1011m x 1 km = 1.5x108 km
103 m
5 1.440x106 g x _?_ =_?_ kg
1.440x106 g x 1 kg = 1.440x103 kg
103g
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