Download PAC102_10e_12_1 - Interactive Learning Toolkit

Fundamentals of Physics
PH 102 is one third of
a Conceptual Survey of Physics
PH 102 Class Packet
Winter 2012
Outlines and Detailed Review Questions
1
PH102
Chapter-by-Chapter
Lecture/Discussion Topic Outlines
Detailed Review Questions
Two tools to help you grasp the material and participate in the class:
1. Topic outlines of the lecture/discussions chapter by chapter giving a linear
overview of the topics that you can expect to be covered.
2. Longer lists of questions you can use for detailed review in PH 102. They are
meant to cover most of the topics covered in the text (Hewitt, Conceptual
Physics, 10th ed.) and class. Students who have wanted to get the most out of the
class have found them very useful. They can be used to provide a sense of what
you know and don't yet know. They can provide specific questions you can ask if
you want help and aren't sure what to ask.
 Copyright 1987-2008 by Dennis Gilbert, do not copy without permission
2
Students,
Here is a detailed (and pretty complete) listing of review questions and chapter outlines
covering the main and minor concepts from the class experience, including text,
lectures, discussions, assignments, and activities.
Use the questions:

to refresh your memory

to check how well you read the text and get understanding from the class

to prepare for class

to prepare for asking questions

to pinpoint areas of your knowledge needing more work

to keep track of your progress in learning the subject

to support your learning with others

to organize your notes

to organize your understanding
I think you'll find these questions very helpful. Keep up with answering them to avoid
getting overwhelmed by too many. Use them one chapter at a time, as we go over the
subjects in class.
People have generally found these questions more useful than doing exercises at the
end of the chapters. You, therefore, may do the review questions as a substitute for the
exercises, if you'd like.
Use these review questions by yourself or with others. Let me know how useful they
are to you, and how you think they could be improved. There is some space at the end
of the list for you to record your comments throughout the term.
Dennis Gilbert, PH 101,2,3 Curriculum Coordinator
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OUTLINES/DETAILED REVIEW QUESTIONS PH 102
Outlines and supplementary review questions for PH 102, Lane Community College,
organized to the text (Conceptual Physics, 10th edition, Paul Hewitt) and
lectures/activities/labs.
TABLE OF CONTENTS
(4)
To Students .
3
.
.
Heat and Thermodynamics
Overview ideas .
.
.
5
Chapter 15: Temperature, Heat and Expansion .
Chapter 16: Heat Transfer .
.
.
6,7 (Outline, Questions)
.
.
13,14
Chapter 17: Change of Phase .
.
.
19,20
Chapter 18: Thermodynamics .
.
.
25,26
Waves and Sound
Overview ideas .
.
.
31
Chapter 19: Vibrations and Waves .
Chapter 20: Sound .
.
.
.
32,33
.
39,40
Chapter 21: Musical Sounds .
.
.
44,45
Electricity and Magnetism
Overview ideas .
.
.
50
Chapter 22: Electrostatics .
. .
Chapter 23: Electric Current .
Chapter 24: Magnetism .
.
51,52
.
.
58,59
.
64,65
Chapter 25: Electromagnetic Induction .
Comments and Suggestions .
.
.
.
.
68,69
74
4
Heat & Thermodynamics: Overview Ideas
A. In what three ways is the realm of motion in heat and thermodynamics different than
the motion of objects discussed in classical mechanics (PH 101)?
#1
#2
#3
B. Thermodynamic systems involve vast numbers of constituent parts. What are three
consequences of this fact for the theories of heat and thermodynamics?
#1
#2
#3
C. What are three key concepts that the classical view of heat and thermodynamics
defines and carefully distinguishes from each other?
#1
#2
#3
5
15. Temperature, Heat, and Expansion: Brief Overview
Perspective on Heat and Thermodynamics (comments)
New kinds and aspects of motion
Consequences of vast numbers of constituent parts
Three basic concepts to define and differentiate:
thermal energy, temperature, heat
Thermal Energy
Microscopic view:
thermal energy (PE and KE contributions)
Macroscopic view
as part of internal energy
Thermal Energy  Temperature
examples, inc. cup of tea compared to an iceberg
Temperature
Microscopic view
proportional to average translational KE per particle (Kelvin temp.)
Macroscopic view
the existence of the temperature quality
(Extend discussion to temperature scales and expansion, then on to heat.)
Temperature scales
history
definition: 0C, 0F, K
thermometers
Expansion with temperature increase
reasons for
examples, inc. bimetalic strips, metal rods
holes
exceptions: H20 esp., long chain molecules
Heat
Definition: energy transfer by virtue of a temperature difference
units
Heat  Temperature
existence of specific heat
H20’s high specific heat
reasons for differences in specific heats
specific heat related phenomena, inc. weather, common experiences
Heat  Thermal Energy
existence of non-heat energy transfer
Short Example Calculations
(Relating heat transferred, mass of object, specific heat, and temperature
change) E.G.: Ice water diet, Price of candy calories
6
Chapter 15: Temperature, Heat and Expansion
1. What is thermal motion?
2. What is thermal energy?
3. Can thermal energy be kinetic?, and potential? If so, how?
4. What is internal energy?
5. How are the thermal and internal energies of a substance related?
6. What is thermal equilibrium?
7. From the macroscopic point of view, what does it mean that the temperatures of two
systems are equal?
8. From the microscopic point of view, what does it mean that the temperatures of two
systems are equal?
7
9. Give an example of two objects A and B such that A has a higher temperature and
higher thermal energy.
10. Give an example of two objects A and B such that A has a higher temperature but B
has a higher thermal energy.
11. Give an example of two objects A and B which have the same temperature but A
has higher thermal energy?
12. What do the above examples show about the possibility of an equivalence of
thermal energy and temperature?
13. About what time in human history were thermometers invented?
14. Why do temperature scales have two reference points?
15. What reference temperatures define the Celsius temperature scale?
16. What reference temperatures define the Fahrenheit temperature scale?
17. What is the origin of the use of the term "degrees" in the Celsius and Fahrenheit
scales?
8
18. What reference temperatures define the Kelvin temperature scale?
19. What is absolute zero?
20. Since a thermometer only measures its own temperature, what quality (ies) must a
thermometer have so it accurately measures the temperature of something else?
21. What is heat?
22. Can a substance become hotter without adding heat to it? If so, how?
23. Can a substance become colder without it losing heat? If so, how?
24. Which way does heat flow?
25. Why is it incorrect to say that a body contains a certain amount of heat?
9
26. What is the definition of a calorie?
27. What is the definition of a Calorie (i.e. food calorie)?
28. The calorie and the Calorie are units of what?
29. Where did the term "calorie" come from?
30. What are two reasons (one from this chapter, one from later) why temperature is
not equivalent to the thermal energy per particle?
#1
#2
31. What is the specific heat of a substance?
32. Generally speaking, what is the difference in behavior of materials with low and high
specific heats?
33. What are two basic reasons why different substances have different specific heats?
#1
#2
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34. What is the approximately constant value (and units) of the specific heat of water?
(Note: Unless otherwise noted, "water" will refer to liquid water.)
35. How does the specific heat of water compare with the specific heats of other
common substances?
36. What are some consequences of the relatively extreme value of the specific heat of
water?
37. Approximately how high must water be dropped to raise its temperature by 1 0C
upon impact (assuming all the kinetic energy becomes thermal energy upon impact)?
38. What are two reasons why substances generally expand when heated?
#1 (for gases)
#2 (for solids and liquids)
39. Of solids, liquids, and gases, which generally expands the most when heated?, the
least?
40. What are some exceptions to the "rule" that substances expand when heated?
Why does this happen?
11
41. How does the amount of expansion or contraction of a metal depend on the
temperature change?
42. How does the amount of thermal expansion or contraction of a metal depend on its
length?
43. What does a bimetalic strip do when heated? Why?
44. What are some common uses of bimetalic strips?
45. What is the purpose of the gaps (filled with tar) in concrete roadways?
46. How would a mercury-glass thermometer be different if the glass expanded more
with increasing temperature than the mercury?
47. How do the holes in objects change when the objects are heated?
12
48. Why does water contract as it is heated when the water is close to 00C?
49. Why is it important to protect water pipes so they don 't freeze?
50. At what temperature is liquid water most dense?
51. What is the temperature of water at various levels in a pond as it cools (from above)
from 150C until it begins freezing?
52. Why don’t deep bodies of water freeze entirely, even in the coldest of winters?
13
16. Heat Transfer: Brief Overview
Processes of Heat Transfer: Conduction, Convection, and Radiation
Definitions
Conduction
Depends on what?
Insulators
Relation to electrical conductivity
Examples
inc. cup design, temperatures we feel
Convection
Forced and free
Examples
inc. melting flashlight in orbit, wind off lake, cooling of lakes
Depends on what?
An organized process
Why warm air rises
macroscopic view
microscopic view
Why expanding air cools
macroscopic view
microscopic view
Radiation
As electromagnetic waves
Depends on what?
temperature dependence
emission, absorption, reflection: good emitter = poor reflector
appearance of radiation of cold
Examples
inc. cream and coffee cooling problem
frost when air above freezing temperature
Newton’s law of cooling
exponential growth and decay
Solar power
Radiative equilibrium of the Earth
14
Chapter 16: Heat Transfer
1. Name and define three processes of heat transfer.
#1
#2
#3
2. What are some examples of heat conduction?
3. What four things does heat conduction depend on (recall the hiking cup discussion)?
#1
#2
#3
#4
4. What is a poor heat conductor called?
5. Why does a good conductor feel cooler than a poor conductor even though both are
at room temperature?
6. When does a good conductor feel the same temperature as a poor conductor?
7. What accounts for the good insulating properties of wool, fur, and feathers?
8. What accounts for the good insulating property of snow?
9. Why can a person walk over hot coals without getting their bare feet burned?
15
10. Why are good heat conductors often good conductors of electricity?
11. Why do liquids and gases usually transmit heat mainly by convection?
12. Why does a lake cool significantly slower once its surface temperature reaches
40C?
13. What distinction is made between the convection that carries heat from you through
the air, and the convection that carries heat throughout your body?
14. What is the macroscopic explanation of why hot air rises'?
15. Why, from a microscopic viewpoint, does hot air rise? (Note: the book provides only
a macroscopic explanation.)
16. What is the macroscopic explanation of why expanding air cools?
17. Why, from a microscopic viewpoint, does expanding air cool? (Note: the book
explanation can be misleading.)
16
18. In what way is convection an organized process?
19. What are some examples of convection and the effects of convection?
20. Is heat radiation due to radioactivity?
21. What four things does heat convection depend on?
#1
#2
#3
#4
22. What are some other kinds of electromagnetic radiation beside heat radiation?
23. Generally, how does heat radiation depend on the temperature of the object doing
the radiating?
24. What three things does heat radiation depend on?
#1
#2
#3
25. What is the relation among the rates at which a body emits, absorbs, and reflects
heat radiation?
17
26. Why, when a black and a white container are filled with hot (or cold) water, does the
blackened one cool (or warm) faster?
27. How can frost form on objects when the air temperature stays above freezing?
28. How is it that cold objects seem to radiate "cold"?
29. Why do Midwestern wheat farmers prefer deep snows, rather than shallow or no
snow, in harsh winters to protect their fields?
30. What is the greenhouse effect?
31. What is the main reason an actual greenhouse stays so warm?
32. What is Newton's law of cooling?
33. What is "wind chill"? Is there also a "wind heat"?
34. If the surface of the Sun is no hotter than some welding torches, how is it that the
whole Earth can be heated so well by the Sun?
35. How does the average solar power (per area) compare with power need (per area)
to heat or cool the average US house?
18
17. Change of Phase: Brief Overview
Change of Phase (State) - a Process
Liquid <---> Gas: boiling, evaporation, condensation
Liquid <---> Solid: freezing, melting
Solid <---> Gas: sublimation, freezing
Evaporation and Condensation
Evaporation, the process
a cooling process
Condensation, the process
a heating process
Examples
Boiling
The process
contrast with evaporation
as a cooling process
The boiling point
Melting and Freezing
Similarities and differences between liquid - gas changes
Phase diagrams (especially H2O)
H20 exceptional behavior, including regelation
Freezing point lowering by dissolving substances in water
changing the boiling point
Change of State from the Energy Viewpoint
Graph of change of state of water
Latent heat of transformation
heat of vaporization
heat of fusion
Examples, including double boiler operation
Humidity
Saturation level
dependence on temperature
Absolute and relative humidity
Examples
Weather (some aspects)
Fog and clouds
Rain, snow, and hail
Examples, including weather east and west of mountains
of West Coast of North America
19
Chapter 17: Change of Phase (State)
1. What are the specific processes of change of one phase (solid, liquid, gas) to
another?
2. What is evaporation?
3. How is evaporation a cooling process?
4. What is condensation?
5. How is condensation a heating process?
6. How do condensation and evaporation effect us as we step from a shower into a
steamy or dry room?
7. What is the main way boiling is different from evaporation?
8. What is boiling?
9. What determines the boiling point of a liquid?
10. How does the "toy drinking bird" work?
20
11. How does a pressure cooker work?
12. How does a geyser work?
13. Why is boiling a cooling process?
14. How is it that water can be boiling and freezing at the same time?
15. What is freeze-drying?
16. During melting and freezing and during evaporation and condensation, there is a
change in organization of the molecules. What doesn’t change much during melting and
freezing, but does change a lot during evaporation and condensation?
17. What is a phase diagram? And what is it for water?
21
18. What is regelation?
19. Why does regelation occur with ice?
20. Why does an ice skater slide easily over ice?
21. Why does dissolving something (like salt or alcohol) in water reduce its freezing
point?
22. Why does dissolving salt in water lower the boiling point?
23. What happens to the temperature in time as heat is added to water, starting when
the water is ice below 00C? (show on a graph)
24. What is heat of transformation, heat of vaporization, and heat of fusion?
22
25. What obvious evidence is there for water having a heat of vaporization?, a heat of
fusion?
26. Why doesn't the water in a double-boiler boil?
27. How is the change of state of a fluid used in the operation of a refrigerator?
28. How does a heat pump work?
29. How does the formation of snow or rain affect the temperature of the air?
30. What does the existence of heats of transformation have to do with the question of
the equivalence of heat and temperature?
31. What is meant by saying that air is saturated with water vapor?
32. When air is heated, can it hold more, the same, or less, water vapor? Why?
33. What is absolute humidity?
23
34. What is relative humidity?
35. What are fogs and clouds and what is the main difference between them?
36. Why does dew form?
37. How are snowflakes formed?
38. How is hail formed?
39. Why, on the West Coast of North America, is it generally hotter east of the
mountains in spring and summer?
40. Why is the relatively rare easterly wind on our west coast sometimes exceptionally
warm (especially noticeable at night), with the air warmer than it was on the east side of
the Cascades or Sierra Nevada mountain ranges?
24
18. Thermodynamics: Brief Overview
Thermodynamics
Definition
A macroscopic theory
The First Law of Thermodynamics
Relation of heat, work, and internal energy
As a specific case of conservation of energy
Historical significance
end of "caloric" theory of heat
Examples of phenomena explained by the 1st Law
including heating during rapid compression
The Second Law of Thermodynamics
Concerns of the 2nd Law
irreversibility of processes
the quality of energy
The 2nd Law in terms of heat
examples
The 2nd Law in terms of heat and work - heat engines
energy diagram
of heat engines
of refrigerators
ideal efficiency
examples
The 2nd Law in terms of organization
entropy
caution: 2nd Law applies to
- systems, not processes
- closed, not open, systems
examples (including misuse of 2nd Law)
Spontaneous Organization
Necessary conditions for occurrence
open systems
far from equilibrium
Description of process
order through fluctuations
dissipative structures
Common misunderstandings of spontaneous organization
as a "violation" of 2nd Law of Thermodynamics
impossibly rare according to a naive view of development by chance
25
Chapter 18: Thermodynamics
1. What is thermodynamics?
2. What is the limiting lowest possible temperature on the Celsius scale?, the Kelvin
scale?
3. What are some forms of energy making up internal energy besides thermal energy?
4. What are some forms of energy of an object which are not part of its internal
energy?
5. What is the First Law of Thermodynamics (in the language of thermodynamics)?
6. What more general law is the First Law of Thermodynamics an instance of?
Historically speaking, the First Law affirmed what?, rejected what?
7. What was the final attempt to save the caloric theory of heat, and how was the
attempt shown to be incorrect?
26
8. What is an adiabatic process?
9. Give some examples of (essentially) adiabatic processes?
10. How, in general, are adiabatic processes able to occur in nature (two reasons)?
#1
#2
11. What happens to the temperature in an adiabatic process? What does it depend
on?
12. Why, according to the First Law of Thermodynamics, does rising air cool?
13. Why must the very cold air from outside a high flying plane be cooled by air
conditioning when it’s brought inside the plane?
14. What is a temperature inversion and how is one typically produced?
15. What is "thermal pollution"?
27
16. What is the Second Law of Thermodynamics in terms of heat flow?
17. What is the Second Law of Thermodynamics in terms of the work done by a heat
engine?
18. What is the maximum efficiency of a heat engine?
19. Where does the fuel energy of a car go? Roughly how much goes to cooling,
exhaust, and energy used?
20. Of the energy used (see above) by a car, how specifically is it used?
21. How is it possible to have the ideal efficiency of a heat engine approach 100%?
22. What does the Second Law of Thermodynamics say about energy?
28
23. What is the Second Law of Thermodynamics in terms of organization?
24. What is entropy?
25. What is a closed system?, an open system?
26. What determines the direction of time from the perspective of thermodynamics?
27. What are some examples of spontaneous organization of matter?
28. What are two necessary conditions for order to spontaneously develop in a finite
system?
#1
#2
29. What are dissipative structures?
30. What are some examples of dissipative structures?
29
31. What is the naive view of development by chance?, what does this view overlook?
32. What are some examples of physical phenomena that illustrate the error of the
naive view of development by chance?
33. How is the Second Law of Thermodynamics sometimes used to discredit the theory
of spontaneous evolution of life on earth or as evidence of the existence of a
creator/designer (e.g. god)?
34. How is it invalid to use the Second Law of Thermodynamics for either of the above
purposes?
30
Waves & Sound: Overview Ideas
(Note: Answers to most of these questions provide more of a summary overview than
an introductory overview.)
A. What are the wave phenomena discussed in this section (name nine)?
#1
#2
#3
#4
#5
#6
#7
#8
#9
B. What additional wave phenomena will be explored later when light is discussed
(name three)?
#1
#2
#3
C. What is the main distinction between light waves and the waves discussed in this
section of the course?
D. What are the characteristics of a vibration (list three)?
#1
#2
#3
E. What are the characteristics of a periodic wave (list eight, some of which are related
to others)?
#1
#2
#3
#4
#5
#6
#7
#8
31
19. Vibrations and Waves: Brief Overview
Vibrations
Definition, examples
Simple harmonic motion
conditions for
sine curve
Description
amplitude, frequency and period, phase
Waves in General
Definition, examples
Waves in a medium
Contrast with vibration, with objects of classical mechanics
Periodic Waves
Importance of
Definition and description
amplitude, frequency and period, phase,
wavelength, velocity, and sine curve character
Relation of period & frequency; frequency, wavelength & velocity
Energy and momentum
intensity dependence on amplitude
Wave Pulses and Packets
Dispersion, group and phase velocity
Transverse and Longitudinal Waves
Definition, examples
Polarization (comment only, more in study of light)
Interference
Superposition principle
Constructive and destructive
Interference patterns
Standing Waves
Conditions for
Description, examples
Doppler Effect
Explanation, examples
Shock Waves
Wave barriers, bow waves
Sonic booms
32
Chapter 19: Vibrations and Waves
1. What is a wave?
2. What is transported by a wave even though it might not be expected from classical
mechanics since waves don't have a mass?
3. What are some other ways a wave is different from other objects studied in classical
mechanics?
4. How does the velocity of a wave depend on the velocity of the source of the wave?
5. What is a vibration?
6. What is the difference between a vibration and a wave?
7. What is required as a source of waves?
8. What are some examples of simple harmonic motion?
33
9. What kind of force produces simple harmonic motion?
10. What is the relation between simple harmonic motion and a sine curve?
11. What is the relation between simple harmonic motion (or a sine curve) and the
motion of a point on the edge of a rotating disk?
12. What does the period of a pendulum depend on, and how is the period related to
these quantities?
13. Why do short-legged animals walk with quicker strides than long-legged animals?
14. How does the frequency of a wave compare to the frequency of its source (in the
frame of reference in which the source is at rest)?
15. What is a periodic wave?
16. Why are periodic waves so useful to study and understand?
17. For a periodic wave, what is the wave's frequency, wavelength, velocity, period, and
amplitude? (Make a sketch and label.)
34
18. What is the relationship between a periodic wave’s period and frequency?
19. What are the units of frequency?
20. What does the phase of a wave describe?
21. What is meant by two waves being "in phase" and "out of phase"?
22. What is the relationship among a periodic wave's velocity, frequency, and
wavelength?
23. What makes a wave transverse?
24. What are some examples of transverse waves?
25. What makes a wave longitudinal?
26. What are some examples of longitudinal waves?
27. How is it possible for a wave to be neither (completely) longitudinal nor transverse
(or is it possible)?
28. Give an example of a wave that is neither (completely) longitudinal nor transverse (if
it is possible)?
35
29. What is polarization?
30. Why is polarization only possible with transverse waves?
31. In what way do waves obey the superposition principle?
32. What is constructive interference?, destructive interference?
33. What is an interference pattern?
34. What is diffraction?
35. What are some examples of diffraction (other than diffraction of light)?
36. What is a wave packet?, and how is it related to periodic waves?
37. In the propagation of wave packets, what is group velocity?, phase velocity?
36
38. What is the dispersion of a wave packet?, and what causes it?
39. What does it mean that a medium is dispersive in its propagation of waves?
40. What is a standing wave formed of?
41. What are the nodes of a standing wave?
42. How can you figure out the wavelength of the waves in a standing wave with nodes
at each end?
43. What are some examples of standing waves?
44. What is the doppler effect?
45. In what situations can the doppler effect occur?
46. What are some examples of the doppler effect?
37
47. What is a wave barrier?
48. What are bow waves? When are they produced? What are they a superposition of?
49. What is the shape of a bow wave and how does the shape depend on the velocity
of the object producing it?
50. What is the shape of, and the pressure distribution in, a shock wave produced by a
supersonic aircraft?
51. When does a sonic boom occur?
52. What are some examples of sonic booms produced by things other than aircraft?
53. What is (are) the source(s) of sound of a sonic boom?
38
20. Sound: Brief Overview
Sound
Nature of a sound wave
in air
in other media
Amplitude
Transverse or longitudinal character
Velocity
Frequency
infrasonic
ultrasonic
Wavelength
Adiabatic process
Refraction (of Sound)
Definition and explanation
conditions for occurrence
Examples
Reflection (of Sound)
Definition and explanation
conditions for occurrence
the viewpoint of boundary conditions
Reverberation
Examples (including with doppler effect)
Energy in Sound Waves
Common magnitudes
Dissipation as heat (to be continued in next chapter)
Resonance
Definition and explanation
Conditions for occurrence
forced vibration and natural frequency
Examples
Interference and Sound
(continuation of discussion of interference)
Beats
Definition and explanation
Examples
Interference pattern associated with beats
“Visual beats"
39
Chapter 20: Sound
1. What is the nature of sound in air?
2. In the two common descriptions of sound waves, what does the amplitude of the
wave correspond to? What are other kinds of amplitudes of a sound wave?
3. With regard to sound in air, what is meant by condensation and rarefaction?
4. Do the condensations and rarefactions in a sound wave travel in the same or
opposite directions from one another?
5. On what two characteristics of a sound wave does the loudness of sound depend?
6. On what wave characteristic(s) does the pitch of sound depend?
7. What is infrasonic sound?
8. What is ultrasonic sound?
9. What is meant by saying sound in air travels adiabatically?
10. What is a reasonable argument for why common sound travels adiabatically to a
high degree?
40
11. What other media can conduct sound and how do they compare with air in terms of
the speed of sound and the ease of conductivity?
12. What approximately is the speed of sound in air?
13. What approximately is the wavelength of a mid-range sound in air?
14. On what things (name two) does the speed of sound in air depend?
#1
#2
15. What is refraction?
16. Why does refraction occur?
17. Under what conditions can refraction of sound occur in air (specify two)?
#1
#2
18. What is an echo?
19. What is reverberation?
20. How does ultrasound detect movement in a body?
21. How does radar detect car movement on the highway?
22. What sort of thinking (using boundary conditions) is used to eliminate consideration
of exactly what goes on at a reflection boundary?
41
23. How does the reflected wave depend on fixed and free boundary conditions?
24. What approximately is the speed of sound in water? in steel?
25. How is the depth of water figured out from the time it takes a signal to bounce off
the ocean bottom?
26. Do sound waves carry very much energy compared to the other common amounts
of energy emitted around us (say by a flashlight)?
27. What happens to sound energy?
28. How does the dissipation of sound energy depend on the frequency of the sound?
29. Which travels further, sound of low or high frequencies? Why?
30. Why do foghorns have a low frequency?
31. What is forced vibration?
32. What is a natural frequency of an object?
33. What is resonance?
42
34. When does resonance occur?
35. What are some examples of resonance phenomena?
36. What are beats?
37. What is the relationship of the beat frequency to the frequencies of two sounds of
slightly different frequencies producing the beats?
38. What are some examples of the analogous "visual beats" phenomena?
39. How is the beats phenomena used (give several examples)?
40. What sort of interference pattern is produced by two separated sources of periodic
waves of slightly different frequencies (so that beats occur)?
43
21. Musical Sounds: Brief Overview
Musical Notes (Comments)
On the distinction between music and noise
On the limits of our discussion
Three Dimensions of Musical Notes
Pitch
hearing range and ordering
Loudness
intensity and intensity level
decibels
hearing
Quality
fundamental and overtones
harmonics
independence of phase of harmonics or overtones
Interrelation of pitch, quality and loudness
Examples
Production of Musical Notes
Major classes of musical instruments
Examples
Musical Scales
Basis for scales
Intervals between notes
Diatonic major scale
Equitempered scale
evolution from diatonic major scale
Analysis (Breaking Up into Components) of Sound
Fourier analysis
Implications for recording and reproduction of sound
Digital and Analog Recording
Basis of each
binary number system
Laser disc players
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Chapter 21: Musical Sounds
1. Practically speaking, in general how are different musical notes created in acoustic
instruments?
2. How is pitch related to frequency?
3. What is the intensity of sound and how is related to loudness?
4. What is the relative loudness of sound called and what units is it measured in?
5. What is the sound level of a whisper?
6. What is the threshold of hearing?
7. What is the threshold of pain (or feeling)?
8. At continual exposure (8 hours a day, five days a week) to what sound level does
physiological hearing damage definitely begin to occur?
9. What is the practical significance of the relation of the above two sound levels?
10. Why is hearing damage common in our society today?
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11. On what does the quality - or timbre - of a tone depend?
12. In what way are the same notes from two different instruments the same (one way)
and different (two ways)?
13. What is the fundamental of a musical note?
14. What are the overtones of a musical note?
15. What are the harmonics of a musical note?
16. What pitch is heard if the first overtone is more intense than the fundamental?
17. What pitch is heard if the fundamental is entirely removed?
18. What are the three classes of conventional acoustic musical instruments?
#l
#2
#3
19. What are the modes of vibration of a guitar string?
20. What are the modes of vibration of a drum surface?
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21. What are the modes of vibration of the air in an organ pipe open at one end?
22. What are the modes of vibration of the air in an organ pipe open at both ends?
23. How are the sounds from electronic musical instruments produced?
24. What characteristic(s) determine the pleasantness of musical notes?
25. What is a musical scale?
26. What is the diatonic major scale?
27. What is the musical interval between two notes?
28. What happens to the frequency in each consecutive octave on a piano?
29. What are half intervals and whole intervals on the diatonic scale?
30. What is meant by playing a tune in a different key?
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31. What is accomplished by having the black keys on a piano keyboard?
32. What is the advantage of the equitempered scale?
33. How many notes and intervals are there in one octave?
34. What is the ratio between all successive notes in the equitempered scale?
35. What musical note is the same on the diatonic and equitempered scales?
36. What is Fourier analysis? (Give an example, too.)
37. The notes of a piano keyboard range in the hundreds of cycles per second, but to
duplicate the music of a piano composition accurately requires a sound system to have
a range of frequencies into the thousands of cycles per second. Why?
38. What is the use of a high-fidelity sound system having a frequency range beyond
the range of human hearing?
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39. How are the frequencies produced by a typical speaker related to the diameter of
the speaker?
40. Why do we hear low notes from small speakers?
41. How can audible sound be carried by ultrasonic sound, and what are some of the
consequences and uses of this phenomena?
42. What is a digital recording of sound?
43. What is an analog recording of sound?
44. What is the number system called binary?
45. Approximately how many digital signals per second are sampled from a laser disc?
46. How does a laser disc player work?
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Electricity & Magnetism: Overview Ideas
A. How (briefly) have the concepts of electricity and magnetism arisen and evolved as
explanations of a particular kind of motion of objects?
B. In what sense is the electrical (including magnetic) interaction viewed as a historical
event of the universe?
C. In what two ways is the electrical interaction of tremendous practical importance?
#1
#2
D. In what three ways is the electrical interaction of significant broad intellectual
importance?
#1
#2
#3
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22. Electrostatics: Brief Overview
General Perspective on Electricity and Magnetism
Evolution of the concepts
in terms of fundamental interactions
Practical importance of the electrical interaction
electronic age
chemistry and biology
The intellectual significance of the concepts
practicality and common form of interaction
rich example of the historical evolution of concepts
basis for further evolution
Structure of our study of the subject
electricity, magnetism, electricity and magnetism
Electrical Charges and the Electrical Interaction
Charges as the bearers of the electrical interaction
one kind of charge, but positive and negative
Charges in nature
nucleon level and larger
sub-nucleon level
two new questions raised by electrical understanding of atoms
The electrostatic interaction – Coulomb’s Law
comparison to Newton's Law of Gravity
The Ability of Materials to Transport Charge
Insulators and conductors
great range of conductivity
Superconductors
Semiconductors
Processes of Charging
By friction
By contact
By induction
The Electric Field
The concept of a field
compared to action at a distance
Representation of the electric field by lines of force
Electric Potential
Definition
distinction from electric potential energy
analogy to gravitational potential
Units
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Chapter 22: Electrostatics
1. What do electrical forces have to do with chemistry?
2. Why is the gravitational force the predominant force between celestial bodies even
though the electrical force is long range like gravity and is much stronger than gravity?
3. What, roughly, is the composition of an atom?
4. What is the charge of a "normal" atom?
5. What are the charges inside an atom?
6. What are two important questions about atoms that cannot be answered through an
understanding of the electrical force?
#1
#2
7. How does the electrostatic force between two charges depend on the size of the
charges (i.e. amount of charge) and the distance between them?
8. How is this relationship expressed mathematically?
9. This relationship is similar in form to the expression for the force of gravitational
attraction; but what are two major differences?
#1
#2
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10. What is the standard unit of electrical charge?
11. How does one standard unit of electrical charge compare to the net amounts of
charge a person occasionally picks up or loses?
12. What are some common phenomena that show there is a vast difference in the
electrical conductivity between conductors and insulators?
13. Why is a person not electrically shocked while inside a car struck by lightning?
14. At the microscopic level, what is the difference between (solid) conductors and
insulators?
15. What is a superconductor?
16. What is a semiconductor?
17. What are some uses of semiconductors?
18. How is semiconductor material used in the photocopy process?
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19. What are three methods of charging an object?
#1
#2
#3
20. What are examples of each method of charging?
#1
#2
#3
21. How is the charge of an (everyday) object explained in microscopic terms?
22. What is the principle of conservation of charge?
23. What is an example of a process that shows the conservation of charge?
24. For ordinary objects, what is the quantum of the amount of charge, and the
quantum of charge?
25. What is the quantum of charge and the quantum of the amount of charge of the
particles inside a proton or neutron?
26. How can an atom be electrically polarized?
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27. How can an insulator partially shield a charge?
28. In contrast to insulators, how does a conductor fully shield a charge?
29. How does empty space slightly shield a charge?
30. Why does a comb run through dry hair attract pieces of paper? And then after
sticking to the comb for a while, why do the pieces of paper fly off the comb?
31. Why does a balloon rubbed on your hair stick to the ceiling?
32. In general, how can an electrically neutral object be attracted to a charged object?
33. In general, how can there be electrical attraction between two neutral objects?
34. What does lightning have to do with charges and electrical forces?
35. How does a lightning rod work?
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36. What is the difference between viewing the electrical force in terms of interacting
charges acting at a distance via Coulomb's Law, and viewing the electrical force in
terms of an electric field?
37. How is the electric field at a point defined?
38. What is one clear advantage of the electric field point of view?
39. Why is the electric field a vector field?
40. How is the electric field (both its magnitude and direction) represented in terms of
"lines of force"?
41. What does the electric field look like around a positive charge, a negative charge,
two positive charges, two negative charges, a positive and a negative charge, and two
oppositely charged parallel plates?
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42. What is the electric potential energy of a charge at a location?
43. How is the electric potential at a location defined?
44. Why does the electric potential always refer to electric potential differences?
45. What is the standard unit of potential?
46. What is the relation between electric potential and electrical potential energy?
47. Which direction does an electron tend to travel, toward a higher potential or a lower
potential?
48. Which direction does a proton tend to travel, toward a higher potential or lower
potential?
49. What does it mean to say a battery is 12 volts?
50. How does a Van de Graaff generator work?
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23. Electric Current: Brief Overview
Flow of Charge - Current
Direction and cause
emf
units: volts
Resistance
units: ohms
Ohm’s Law: I = V/R
electric shock
Direct and alternating current
Microscopic view
electron velocity
electron drift velocity
velocity of changes in electric field
Examples, including lemon battery
Electric Power
Units: watts, kilowatt-hours
Calculations: P = IV
Examples, including the cost of a lightning bolt
Electrical Circuits
Series circuits
characteristics
advantages and disadvantages
Parallel circuits
characteristics
advantages and disadvantages
overloading and circuit breakers
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Chapter 23: Electric Current
1. In general, what is necessary for charge to flow through a conductor?
2. What is the statement about electrical systems that is analogous to the statement
that "Water seeks its own level"?
3. Which way does (positive) charge flow?
4. What is necessary to sustain a flow of charge in a conductor?
5. What is an emf?
6. What is the main advantage of chemical batteries and generators over electrostatic
devices for generating or storing charge?
7. What is an electric current?
8. What is the standard unit for electric current?
9. What is the charge on a conductor carrying electric charge?
10. What is the cause of resistance in a conductor?
11. How does the resistance of a wire depend on its length and thickness?
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12. What are the units of resistance?
13. What is the relationship among current, potential difference (voltage), and
resistance in many materials?
14. What are some examples of systems that do not obey Ohm's Law?
15. What are some examples of systems that do obey Ohm's Law?
16. What causes an electric shock?
17. What does the damage in an electric shock?
18. What two kinds of damage are done to an electric shock victim?
19. Why is it unsafe to stand in water while handling electrical devices?
20. Why can a bird sit on a high voltage wire without getting electrocuted?
21. In sockets with three connections, what is the purpose of the third connection?
22. What is meant by direct current and alternating current?
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23. What is the frequency of household current in the US?
24. What is the voltage of household current in the US?
25. What advantage of a.c. current accounts for its popular use?
26. About how fast is electric energy passed in a conductor?
27. About how fast are the individual electrons in a conductor?
28. About how fast do electrons drift, on the average, in normal currents in a
conductor?
29. What flows from the power company to your home?
30. What is the relationship between the power, the current, and the voltage across
common (non-semiconductor) electrical devices?
31. For common (non-semiconductor) electrical devices, what are the values of their
power used, current, resistance, and voltage across the device? (Give some
examples.)
32. What are the units of power used in studying electricity?
33. What are the units of power expressed in more familiar, and more basic, units?
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34. How can the cost of using particular appliances be determined?
35. What kind of unit is a kilowatt-hour?
36. What is an electrical circuit?
37. What distinguishes an open circuit from a closed circuit?
38. What is a series circuit?
39. What is a parallel circuit?
40. What does “line current” mean?
41. What are the advantages and disadvantages of a series circuit?
42. What are the advantages and disadvantages of a parallel circuit?
43. What are the important characteristics of a series circuit?
44. What are the important characteristics of a parallel circuit?
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45. How can the line current be figured out when several devices are operating in
parallel?, in series?
46. What is meant by a parallel circuit being overloaded?
47. How does a fuse work?
48. How does a circuit breaker work?
49. What is the meaning and origin of the term "short circuit"?
50. What is the difference in performance between a 12-volt car battery and eight 1½
volt flashlight batteries put in parallel so their total voltage is 12 volts? Why?
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24. Magnetism: Brief Overview
The Unity of Electrical and Magnetic Interactions (Comments on Special Relativity and
the historical understanding of magnetism)
Production of Magnetism
In general
Ferromagnetism
microscopically
atomic sources
domains
magnetization and demagnetization
The Magnetic Field
Magnetic poles
attraction and repulsion
origin of names
magnetic monopoles
Field of the Earth
declination
sources
history
Effect of Magnetism on Charges
Dependence on charge and velocity
radiation belts
northern lights
cosmic ray intensity
Miscellaneous Magnetism Topics
Biomagnetism
Speculated connection to evolution
Other
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Chapter 24: Magnetism
1. In what way are both electrical and magnetic forces actually different aspects of the
same thing?
2. In general, what produces a magnetic field?
3. Specifically, what produces the magnetic field of an iron magnet?
4. Which usually has the biggest effect in ferromagnetism, the electron’s orbital motion,
or the electron’s spin?
5. What are magnetic domains?
6. Why is not every piece of iron a magnet?
7. What are two ways to weaken an iron magnet?
#1
#2
8. What does the magnetic field around a bar magnet look like?
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9. How is the magnetic force attractive, and how is it repulsive?
10. There are two kinds of electrical charges and two kinds of magnetic poles, but how
are these pairs fundamentally different?
11. What is a magnetic monopole?
12. How can a magnet attract a piece of iron that is not a magnet?
13. How did the north and south poles of magnets get these names?
14. What does the magnetic field of the Earth look like?
15. What magnetic poles are at the geographic poles of the Earth?
16. What does magnetic declination refer to?
17. What are two likely sources of the earth's magnetic field?
#1
#2
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18. In what ways has the magnetic field of the earth changed?
19. How are people able to detect the changes in the earth's magnetic field that
happened millions of years ago?
20. How is a charge's velocity, both in magnitude and direction, affected by a magnetic
field?
21. How does the earth's magnetism help explain its radiation belts?
22. What does the magnetic field of the earth have to do with the aurora borealis
(northern lights)?
23. How does the earth's magnetic field affect the intensity of cosmic rays hitting the
earth's surface?
24. What has been speculated as a connection between the evolution of life on earth
and changes in the earth's magnetic field?
25. What are some examples of the use of magnetism by animals?
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25. Electromagnetic Induction: Brief Overview
Magnetic Field Produced by Current
Review and examples
Current Produced by a Magnetic Field
Preliminary considerations
the necessity of work to get a current
related process: magnetic force on current carrying wire
Electromagnetic induction
Faraday’s Law: the amount of current
Lenz’s Law: the direction of current
Electric Motors and Generators
Close relation of motors and generators
“common” kinds
examples of motors and generators
magnetohydrodynamic (MHD) kinds
examples of motors and generators
Transformers
Operating principles
Primary-secondary voltage relation
Vp/Np = Vs/Ns
Primary-secondary power relation
VpIp = VsIs
Power transmission
Self-Induction (“back emf”)
The process, examples
Field Induction (Introduction)
In Perspective
Critical comments on the author’s conclusion
- theory not equivalent to the phenomena
- knowledge not equivalent to application of the knowledge
- scientific progress doesn’t necessarily lead social progress
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Chapter 25: Electromagnetic Induction
1. What does the magnetic field look like around a current-carrying wire?
2. What does the magnetic field look like around a current-carrying loop?, a current
carrying coil?
3. Why is the magnetic field strength greater inside a current-carrying loop of wire
compared to the wire being straight?
4. Why does placing a piece of iron in a current-carrying coil increase the magnetic field
intensity?
5. What is a superconducting magnet?
6. What effect does a magnetic field have on a current-carrying wire?
7. How does this effect - referred to above - depend on the direction of the current and
the direction of the field, and when is the effect a maximum?
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8. How does an electric motor work?
9. How does a galvanometer work?
10. In what way is a galvanometer similar to an electric motor?
11. How are the motor effect and the generator effect similar?
12. What instrument measures current?
13. What instrument measures potential difference?
14. What is electromagnetic induction?
15. On what does the induced voltage in electromagnetic induction depend?
16. How is "change" necessary for electromagnetic induction occurring?
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17. What are examples of three different processes of electromagnetic induction?
#1
#2
#3
18. What general principle determines the direction of the induced current?
19. What is an electrical transformer?
20. What exactly does a transformer “transform”?
21. Why does a common transformer require alternating current?
22. What is the distinction between the primary and secondary coils of a transformer?
23. What is different about the functions of a step up and a step down transformer?
24. What is the relationship among the primary voltage, the secondary voltage, the
number of primary loops, and the number of secondary loops?
25. Why can, or why can’t, an efficient transformer step up energy?
26. What denotes the rate at which energy is transferred?
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27. How are the primary current and the secondary current related?
28. What physical principle underlies the relationship between the primary and
secondary current?
29. What is self-induction?
30. Why is the self-induced voltage commonly called the "back emf"?
31. What is a common and dangerous effect of self-induction?
32. How do conventional generators produce electric power?
33. How does a conventional electric motor compare to a conventional generator?
34. How do MHD (magnetohydrodynamic) generators produce electric power?
35. What kind of "motor" is the "reverse" of the MHD generator?
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36. What are the principal differences between an MHD generator and a conventional
generator?
37. Why is there an advantage to running power lines at high voltages?
38. At about what voltage is power carried from power plants to cities?
39. What is field induction?
40. What is Faraday's Law?
41. What Law is the "reverse" counterpart to Faraday's Law?
42. What is induced by the rapid alteration of a magnetic field?
43. What is induced by the rapid alteration of an electric field?
44. What three key distinctions does Hewitt fail to make in getting to the conclusion that
social events such as the American Civil War are insignificant when compared to
scientific discoveries such as the discovery of the electromagnetic laws?
#1
#2
#3
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Comments and Suggestions
Please write down your thoughts on the value of these review questions as you use
them throughout the term. Also, put down any suggestions you have for making them
more helpful to the learning process. Thanks.
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