Deck 20: Sound

Question 1

The explanation for refraction must involve a change in

A)frequency.
B)wavelength.
C)speed.
D)All of the above choices are true.
E)None of the above choices are true.

Answer 1

speed.

Question 2

Compressions and rarefactions normally travel in

A)the same direction in a wave.
B)opposite directions in a wave.
C)directions that are at right angles to the wave direction.

Answer 2

the same direction in a wave.

Question 3

A sound source of high frequency emits a high

A)speed.
B)amplitude.
C)pitch.
D)all of these
E)none of these

Answer 3

pitch.

Question 4

A dolphin perceives its environment by the sense of

A)sight.
B)sound.
C)both sight and sound.
D)neither sight nor sound.

Question 5

When the speed of sound near the ground is greater than it is at higher altitudes,the sound tends to be bent

A)upward.
B)downward.
C)to the left.
D)to the right.
E)None of the above choices are correct.

Question 6

The speed of a sound wave in air depends on

A)its frequency.
B)its wavelength.
C)the air temperature.
D)All of the above choices are correct.
E)None of the above choices are correct.

Question 7

A wave having a frequency of 1000 hertz vibrates at

A)less than 1000 cycles per second.
B)1000 cycles per second.
C)more than 1000 cycles per second.

Question 8

Refraction of sound can occur in

A)air.
B)water.
C)both air and water.
D)neither air nor water.

Question 9

A sound wave is a

A)longitudinal wave.
B)transverse wave.
C)standing wave.
D)shock wave.
E)None of the above choices are correct.

Question 10

We are best at hearing

A)infrasonic sound.
B)ultrasonic sound.
C)both infrasonic and ultrasonic sounds.
D)None of the above choices are true.

Question 11

The approximate range of human hearing is

A)10 hertz to 10,000 hertz.
B)20 hertz to 20,000 hertz.
C)40 hertz to 40,000 hertz.
D)Actually all of these - depends on the hearing ability of the person.

Question 12

Reverberation is actually a case of

A)sound interference.
B)forced vibrations.
C)re-echoed sound.
D)resonance.
E)none of the above

Question 13

The source of every sound is something that is

A)vibrating.
B)moving.
C)accelerating.
D)undergoing simple harmonic motion.
E)a net emitter of energy.

Question 14

Double the frequency of sound and you also double its

A)wavelength.
B)speed.
C)amplitude.
D)all of these
E)none of these

Question 15

Sound waves cannot travel in

A)air.
B)water.
C)steel.
D)a vacuum.
E)any of the above media

Question 16

Double the frequency of a sound and you halve its

A)wavelength.
B)speed.
C)amplitude.
D)all of these
E)none of these

Question 17

In perceiving its environment,a dolphin makes use of

A)echoes.
B)the Doppler effect.
C)ultrasound.
D)All of the above choices are correct.
E)None of the above choices are correct.

Question 18

Sound travels faster in air if the air temperature is

A)warm.
B)cold.
C)average.

Question 19

Compressions and rarefactions are characteristic of

A)longitudinal waves.
B)transverse waves.
C)both longitudinal and transverse waves.
D)none of the above.

Question 20

Sound travels faster in

A)air.
B)water.
C)steel.
D)a vacuum.
E)Sound travels at about the same speed in all of the above media.

Question 21

The phenomenon of beats results from sound

A)refraction.
B)reflection.
C)interference.
D)all of these
E)none of these

Question 22

The energy of sound in air eventually becomes

A)increased internal energy of the air.
B)weaker and weaker until it disappears.
C)cancelled by destructive interference.
D)cancelled by both destructive and constructive interference.

Question 23

Sound refraction depends on the fact that the speed of sound is

A)constant.
B)variable.
C)proportional to frequency.
D)inversely proportional to wavelength.
E)None of the above choices are correct.

Question 24

In designing a music hall,an acoustical engineer deals mainly with

A)modulation.
B)forced vibrations.
C)resonance.
D)beats.
E)wave interference.

Question 25

A base fiddle is louder than a harp because of its

A)thicker strings.
B)sounding board.
C)lower pitch.
D)All of the above are true.
E)None of the above are true.

Question 26

The object with the highest natural frequency is a

A)small bell.
B)large bell.
C)medium size bell.

Question 27

The frequencies of sound that carry farther in air are

A)low.
B)high.
C)ultrasonic.

Question 28

For FM radio,the F stands for

A)frequency.
B)forced vibration at which resonance occurs.
C)foul.
D)female.
E)fax.

Question 29

The wavelengths of sound that carry farther in air are relatively

A)long.
B)short.
C)ultrasonic.

Question 30

In the case of radio,which has the higher frequency?

A)carrier wave
B)sound wave
C)Neither.Both may be of the same frequency.

Question 31

Sound will be louder if a struck tuning fork is held

A)in the air.
B)with its base against a table top.
C)with its prongs in shallow water.
D)in your closed fist.

Question 32

For AM radio,the A stands for

A)acceleration.
B)authorized.
C)amplitude.
D)agony.
E)almost.

Question 33

When you tune a radio to a certain station,you match the frequency of the internal electrical circuit to the frequency of the wanted radio station.In so doing you are employing the principle of

A)forced vibrations.
B)resonance.
C)beats.
D)reverberation.
E)wave interference.

Question 34

Use the following figure to answer the question:
When the handle of a tuning fork is held solidly against a table,the sound becomes louder and the time that the fork keeps vibrating

A)becomes longer.
B)becomes shorter.
C)remains the same.

Question 35

Caruso is said to have made a crystal chandelier shatter with his voice.This is a demonstration of

A)an echo.
B)sound refraction.
C)beats.
D)resonance.
E)interference.

Question 36

A 340-hertz sound wave travels at 340 m/s in air with a wavelength of

A)1 m.
B)10 m.
C)100 m.
D)1000 m.
E)None of the above choices are correct.

Question 37

On some days,air nearest the ground is colder than air that is higher up.On one of these days,sound waves

A)tend to be refracted upward.
B)tend to be refracted downward.
C)travel without refraction.

Question 38

The natural frequency of an object depends on its

A)size,shape and elasticity.
B)size and shape.
C)size and elasticity.
D)shape and elasticity.

Question 39

Which doesn't belong to the same family?

A)infrasonic waves
B)ultrasonic waves
C)radio waves
D)shock waves
E)longitudinal waves

Question 40

The least energy required to produce forced vibration in an object occurs

A)below its natural frequency.
B)at its natural frequency.
C)above its natural frequency.

Question 41

A neon atom has a larger atomic number than a helium atom.At the same temperature and pressure,how does the speed of sound in helium gas compare to the speed of sound in neon gas?

A)greater in neon than in helium
B)greater in helium than in neon
C)the same in both gases
D)depends on the frequency of the sound generated

Question 42

Resonance can be looked at as forced vibration with the

A)least amount of energy input.
B)maximum amount of energy input.
C)matching of wave amplitudes.
D)matching of constructive and destructive interference.
E)minimum beat frequency.

Question 43

A 1056-hertz tuning fork is sounded at the same time a piano note is struck.You hear three beats per second.What is the frequency of the piano string?

A)not enough information to be certain
B)1056 hertz
C)1059 hertz
D)1053 hertz
E)3168 hertz

Question 44

Longitudinal waves of different lengths are traveling though a long metal rod.Those that travel at the greatest speed are

A)the shortest.
B)those of medium length.
C)the longest.
D)impossible to predict without knowing the type of metal.
E)None of the above choices are correct.

Question 45

Which type of radio wave produces the least static in a radio receiver?

A)AM
B)FM
C)Both have equal amounts of static.

Question 46

The beat frequency produced when a 240 hertz tuning fork and a 246 hertz tuning fork are sounded together is

A)6 hertz.
B)12 hertz.
C)240 hertz.
D)245 hertz.
E)None of the above choices are correct.

Question 47

Xenon has atomic number 54,while Krypton has atomic number 36.Given that both gases are at the same temperature,in which medium does sound travel faster?

A)Xenon gas
B)Krypton gas
C)a mixture of both gases
D)the same in either gas

Question 48

Inhaling helium increases the pitch of your voice.One reason for this is that sound travels

A)slower in helium than in air.
B)faster in helium than in air.
C)the same speed in helium,but the wavelength is greater.

Question 49

An explosion occurs 34 km away.Since sound travels at 340 m/s,the time it takes for the sound to reach you is

A)0)1 second.
B)1 second.
C)10 seconds.
D)20 seconds.
E)more than 20 seconds.

Question 50

Two tuning forks produce sounds of wavelengths 3.4 meters and 3.3 meters.Approximately what beat frequency is produced?

A)0)1 hertz
B)1)0 hertz
C)2)0 hertz
D)3)0 hertz
E)4)0 hertz

Question 51

A piano tuner knows that a key on the piano is tuned to the frequency of his tuning fork when he strikes them at the same time and the number of beats he hears each second is

A)0)
B)1)
C)2)
D)3)
E)4)

Question 52

In which one of these media does sound travel the fastest?

A)water vapor
B)water
C)ice
D)steam
E)Sound travels the same speed in each of the above media.

Question 53

Suppose you sound a 1056-hertz tuning fork at the same time you strike a note on the piano and hear 2 beats/second.You tighten the piano string very slightly and now hear 3 beats/second.What is the frequency of the piano string?

A)1053 hertz
B)1054 hertz
C)1056 hertz
D)1058 hertz
E)1059 hertz

Question 54

A general rule for estimating the distance in kilometers between an observer and a lightning bolt is to count the number of seconds between seeing the lightning and hearing it,and dividing by

A)2)
B)3)
C)4)
D)5)
E)none of these

Question 55

Use the following figure to answer the question:
Repeatedly tap the side of a drinking glass with a spoon while filling it with water and you will notice that the pitch of the sound

A)increases.
B)decreases.
C)remains relatively constant.