HOLT PHYSICS test 12A

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Name:______________________________Class:__________________ Date:__________________
Assessment
Chapter Test A
Teacher Notes and Answers
Sound
CHAPTER TEST A (GENERAL)
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compression
frequency
watts per square meter, or W/m2
Resonance occurs when the frequency of a
force applied to an object is the same as the
natural frequency of an object.
25. 547 Hz
Given
v = 684 m/s
L = 62.5 cm
Solution
v
fn = n
2L
At the fundamental frequency (first
harmonic), n = 1, so
v
684 m/s
f1 =
=
= 547 Hz
2L 2(0.625 m)
Original content Copyright © by Holt, Rinehart and Winston. Additions and changes to the original content are the responsibility of the instructor.
Holt Physics
1
Chapter Tests
Name:______________________________Class:__________________ Date:__________________
Assessment
Sound
Chapter Test A
MULTIPLE CHOICE
In the space provided, write the letter of the term or phrase that best completes
each statement or best answers each question.
_____ 1. Sound waves
a. are a part of the electromagnetic spectrum.
b. do not require a medium for transmission.
c. are longitudinal waves.
d. are transverse waves.
_____ 2. The trough of the sine curve used to represent a sound wave corresponds
to a
a. compression.
b. region of high pressure.
c. point where molecules are pushed closer together.
d. rarefaction.
_____ 3. Which of the following is the region of a sound wave in which the density
and pressure are greater than normal?
a. rarefaction
c. amplitude
b. compression
d. wavelength
_____ 4. The highness or lowness of a sound is perceived as
a. compression.
c. ultrasound.
b. wavelength.
d. pitch.
_____ 5. Pitch depends on the ______________ of a sound wave.
a. frequency
c. power
b. amplitude
d. speed
_____ 6. In general, sound travels faster through
a. solids than through gases.
b. gases than through solids.
c. gases than through liquids.
d. empty space than through matter.
_____ 7. At a large distance from a sound source, spherical wave fronts are viewed
as
a. wavelengths.
c. rays.
b. troughs.
d. plane waves.
Original content Copyright © by Holt, Rinehart and Winston. Additions and changes to the original content are the responsibility of the instructor.
Holt Physics
2
Chapter Tests
Name:______________________________Class:__________________ Date:__________________
Chapter Test A continued
_____ 8. The distance between wave fronts of plane waves corresponds to
_____________ of a sound wave.
a. one wavelength
c. one compression
b. two amplitudes
d. one rarefaction
_____ 9. A train moves down the track toward an observer. The sound from the
train, as heard by the observer, is ________________ the sound heard by
a passenger on the train.
a. the same as
c. higher in pitch than
b. a different timbre than
d. lower in pitch than
_____ 10. The Doppler effect occurs with
a. only sound waves.
b. only transverse waves.
c. only water waves.
d. all waves.
_____ 11. The property of sound called intensity is proportional to the rate at which
energy flows through
a. an area perpendicular to the direction of propagation.
b. an area parallel to the direction of propagation.
c. a cylindrical tube.
d. a sound wave of a certain frequency.
_____ 12. The perceived loudness of a sound is measured in
a. hertz.
c. watts.
b. decibels.
d. watts per square meter.
_____ 13. Which of the following decibel levels is nearest to the value that you
would expect for a running vacuum cleaner?
a. 10 dB
c. 70 dB
b. 30 dB
d. 120 dB
_____ 14. A sound twice the intensity of the faintest audible sound is not perceived
as twice as loud because the sensation of loudness in human hearing
a. is approximately logarithmic.
b. is approximately exponential.
c. depends on the speed of sound.
d. is proportional to frequency.
_____ 15. When the frequency of a force applied to a system matches the natural
frequency of vibration of the system, ______________ occurs.
a. damped vibration
c. timbre
b. random vibration
d. resonance
Original content Copyright © by Holt, Rinehart and Winston. Additions and changes to the original content are the responsibility of the instructor.
Holt Physics
3
Chapter Tests
Name:______________________________Class:__________________ Date:__________________
Chapter Test A continued
_____ 16. When an air column vibrates in a pipe that is open at both ends,
a. all harmonics are present.
b. no harmonics are present.
c. only odd harmonics are present.
d. only even harmonics are present.
_____ 17. When an air column vibrates in a pipe that is closed at one end,
a. all harmonics are present.
b. no harmonics are present.
c. only odd harmonics are present.
d. only even harmonics are present.
_____ 18. The wavelength of the fundamental frequency of a vibrating string of
length L is
c. 2L.
a. 1/2 L.
b. L.
d. 4L.
_____ 19. The quality of a musical tone of a certain pitch results from a combination
of
a. fundamental frequencies.
c. transverse waves.
b. harmonics.
d. velocities.
_____ 20. Audible beats are formed by the interference of two waves
a. of slightly different frequencies.
b. of greatly different frequencies.
c. with equal frequencies, but traveling in opposite directions.
d. from the same vibrating source.
SHORT ANSWER
21. The region of a sound wave in which air molecules are pushed closer together is
called a(n) ______________.
_________________________________________________________________
22. The _______________ of a musical sound determines its pitch.
_________________________________________________________________
23. What are the units used to express the intensity of a sound?
_________________________________________________________________
Original content Copyright © by Holt, Rinehart and Winston. Additions and changes to the original content are the responsibility of the instructor.
Holt Physics
4
Chapter Tests
Name:______________________________Class:__________________ Date:__________________
Chapter Test A continued
24. Under what conditions does sound resonance occur?
_________________________________________________________________
_________________________________________________________________
_________________________________________________________________
PROBLEM
25. A wave on a guitar string has a velocity of 684 m/s. The guitar string is
62.5 cm long. What is the fundamental frequency of the vibrating string?
Original content Copyright © by Holt, Rinehart and Winston. Additions and changes to the original content are the responsibility of the instructor.
Holt Physics
5
Chapter Tests
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