Deck 6: Waves and Sound

Question 1

Which of the following radiations has the smallest frequency?

A) Infrared
B) Visible
C) Ultraviolet
D) X-rays

Answer 1

A

Question 2

If a wave has a frequency of 15 Hz, it has a period of

A) 1/15 s.
B) 3.9 s.
C) 225 s.
D) 15 s.

Answer 2

A

Question 3

A series of ocean waves, each 24.0 m from crest to crest and moving past an observer at a rate of 6.0 waves per second, has what speed?

A) 144 m/s
B) 4 m/s
C) 6 m/s
D) 0.25 m/s

Answer 3

A

Question 4

A series of ocean waves are moving past a surfer at a frequency of 40 waves per hour. Approximately how many waves would the surfer expect during 48 minutes?

A) 1920 waves
B) 32 waves
C) 40 waves
D) 50 waves

Question 5

The major difference between transverse and longitudinal waves is the

A) direction of the wave motion.
B) phase difference.
C) direction of the particle displacement with respect to the direction of wave motion.
D) size of the waves.

Question 6

Wave frequency is inversely proportional to

A) amplitude.
B) period.
C) wave velocity.
D) all of these.

Question 7

A disturbance in particle motion perpendicular to the wave velocity is called a

A) transverse wave.
B) acoustic wave.
C) standing wave.
D) longitudinal wave.

Question 8

Which of the following radiations has the smallest wavelength?

A) Infrared
B) Visible
C) Ultraviolet
D) X-rays

Question 9

Wave frequency could be given in

A) 1/s.
B) s^-1
C) Hz.
D) any of these.

Question 10

If a piece of ribbon were tied to a stretched string carrying a transverse wave, how would the ribbon be observed to oscillate?

A) Perpendicular to the wave motion
B) Parallel to the wave motion
C) Neither (A) nor (B)
D) Both (A) and (B)

Question 11

Wave period is the reciprocal of

A) amplitude.
B) frequency.
C) wave velocity.
D) all of these.

Question 12

For a transverse mechanical wave, the particle motion is

A) both parallel and perpendicular to the direction of the wave velocity.
B) parallel to the direction of the wave velocity.
C) perpendicular to the direction of the wave velocity.
D) in all directions.

Question 13

Wave velocity is inversely proportional to

A) period.
B) wavelength.
C) amplitude.
D) all of these.

Question 14

If a wave has a frequency of 6 Hz, it has a period of

A) 1/6 s.
B) 6.5 s.
C) 6 s.
D) 3 s.

Question 15

A disturbance in particle motion parallel to the wave velocity is called a

A) transverse wave.
B) acoustic wave.
C) standing wave.
D) longitudinal wave.

Question 16

If a wave has a period of 0.077 sec, it has a frequency of

A) 1/13 Hz.
B) 3.6 Hz.
C) 169 Hz.
D) 13 Hz.

Question 17

Which of the following radiations has the longest wavelength?

A) Infrared
B) Visible
C) Ultraviolet
D) X-rays

Question 18

Wave amplitude is related to

A) wave velocity.
B) frequency.
C) energy.
D) wavelength.

Question 19

Which of the following characterize(s) a wave?

A) Wavelength
B) Amplitude
C) Period
D) All of these

Question 20

For a longitudinal mechanical wave, the particle motion is

A) parallel to the direction of the wave velocity.
B) perpendicular to the direction of the wave velocity.
C) both parallel and perpendicular to the direction of the wave velocity.
D) in all directions.

Question 21

Electromagnetic waves are

A) longitudinal.
B) reverse.
C) transverse.
D) a combination of these.

Question 22

A sound with a frequency of 25 kHz is in the ______________ region of the sound spectrum.

A) infrasonic
B) ultrasonic
C) audible
D) visible

Question 23

A radar pulse returns 9.0 × 10^-4 s after it was sent out and reflected by an object. What is the separation distance of the radar source and the object?

A) 2.7 × 10⁵ m
B) 1.4 × 10⁵ m
C) 7.4 × 10^-4 m
D) 3.7 × 10^-4 m

Question 24

An increase of 20 dB increases the sound intensity by a factor of

A) 10.
B) 200.
C) 100.
D) 20.

Question 25

Light waves travel fastest in

A) water.
B) glass.
C) a vacuum.
D) air.
E) none of these; they travel at the same speed in all these media.

Question 26

The region of the electromagnetic spectrum with frequencies just less than those in the visible region is the ______________ region.

A) infrared
B) gamma rays
C) radio waves
D) microwaves
E) x-rays

Question 27

Which of the following sound frequencies lie(s) in the audible range?

A) 13 Hz
B) 5 kHz
C) 1 MHz
D) All of these

Question 28

Which of the following sound frequencies lie(s) outside the audible range?

A) 20 Hz
B) 47 kHz
C) 4300 Hz
D) All of these

Question 29

The region of the electromagnetic spectrum with wavelengths just greater than those in the infrared region is the ______________ region.

A) microwaves
B) x-rays
C) gamma rays
D) radio waves
E) ultraviolet

Question 30

Which of the following electromagnetic radiations has the greatest frequency?

A) Ultraviolet
B) Infrared
C) Radio
D) Visible

Question 31

The region of the electromagnetic spectrum with wavelengths just less than those in the ultraviolet region is the ______________ region.

A) x-rays
B) radio waves
C) microwaves
D) infrared
E) gamma rays

Question 32

Sound is a(n)

A) longitudinal wave.
B) electromagnetic wave.
C) transverse wave.
D) standing wave.

Question 33

A sound with a frequency of 11 Hz is in the ______________ region of the sound spectrum.

A) infrasonic
B) ultrasonic
C) audible
D) visible

Question 34

Which of the following sound frequencies lie(s) outside the audible range?

A) 14 Hz
B) 11 kHz
C) 2700 Hz
D) All of these

Question 35

The region of the electromagnetic spectrum with frequencies just greater than those in the ultraviolet region is the ______________ region.

A) x-rays
B) radio waves
C) microwaves
D) infrared
E) gamma rays

Question 36

A sound with a frequency of 1000 Hz is in the ______________ region of the sound spectrum.

A) infrasonic
B) ultrasonic
C) audible
D) visible

Question 37

The radiation given off by the nucleus of an atom is called

A) a microwave.
B) a gamma ray.
C) an X-ray.
D) any of these.

Question 38

Which of the following sound frequencies lie(s) in the audible range?

A) 23 Hz
B) 9 kHz
C) 3100 Hz
D) All of these

Question 39

Which of the following radiations has the greatest frequency?

A) Infrared
B) Visible
C) Ultraviolet
D) X-rays

Question 40

Which of the following sound frequencies lie(s) in the audible range?

A) 26 Hz
B) 27 kHz
C) 1 MHz
D) All of these

Question 41

Standing waves can be set up in a string when two waves that are

A) of the same frequency and amplitude, but are opposite in direction of travel, meet each other.
B) of the same frequency, amplitude, and direction of travel are also 180° out of phase.
C) of the same frequency, amplitude, and direction of travel meet each other.
D) of the same frequency, amplitude, and velocity meet each other.

Question 42

A Doppler red shift indicates

A) a shift toward higher frequencies.
B) a shift toward shorter wavelengths.
C) that a light source is approaching relative to the observer.
D) none of these.

Question 43

A Doppler red shift indicates

A) a shift toward higher frequencies.
B) a shift toward shorter wavelengths.
C) that a light source is receding relative to the observer.
D) none of these.

Question 44

During a thunderstorm, an observer notes that 10 s elapsed between the lightning flash and the sound of the thunder. What is the approximate distance, in miles, from the observer to the lightning?

A) 10 mi
B) 50 mi
C) 2 mi
D) 100 mi

Question 45

A Doppler red shift indicates

A) a shift toward lower frequencies.
B) a shift toward shorter wavelengths.
C) that a light source is approaching relative to the observer.
D) none of these.

Question 46

How many times greater is the speed of infrared light (λ = 800 nm) than the speed of violet light (λ = 400 nm) in a vacuum?

A) 2
B) 1/2
C) 400
D) 1; that is, both have the same speed.

Question 47

The threshold of hearing is

A) 0 dB.
B) 140 dB.
C) 40 dB.
D) 110 dB.
E) 1 dB.

Question 48

A sound level of 19 dB is how many times as intense as one of 10 dB?

A) 8
B) 9
C) 3
D) 18

Question 49

A train sounding its horn is moving toward an observer. The pitch of the horn's sound relative to its normal pitch is

A) lower.
B) sometimes higher and sometimes lower.
C) higher.
D) the same.

Question 50

Resonance occurs when

A) two different objects vibrate with different frequencies.
B) two different objects produce beats.
C) an object having a certain natural frequency is set in vibration by a second object vibrating at that frequency.
D) an object produces a sound.

Question 51

Light can travel to Earth from a distant star, but sound cannot. Why is this?

A) Light is an electromagnetic wave, and sound requires a medium.
B) The Sun does not make sound.
C) Light is a longitudinal wave, and sound is a transverse wave.
D) The statement is false; both light and sound can travel in empty space.

Question 52

For the Doppler effect to occur, there must be

A) a moving source.
B) a moving observer.
C) relative motion between a source and an observer.
D) no motion.

Question 53

How many times greater is the speed of red light (λ = 700 nm) than the speed of violet light (λ = 400 nm) in a vacuum?

A) 1.75 , the first color of light is faster
B) 0.57 , the second color of light is faster
C) 3.00 x 10⁸ , the first color of light is faster
D) 1.00 , both colors of light have the same speed
E) 3.00 x 10⁸ , the second color of light is faster

Question 54

A Doppler red shift indicates

A) a shift toward higher frequencies.
B) a shift toward longer wavelengths.
C) that a light source is approaching relative to the observer.
D) none of these.

Question 55

An increase of 40 dB increases the sound intensity by a factor of

A) 1000.
B) 40000.
C) 10000.
D) 4000.

Question 56

The intensity of a 50-dB whistle is doubled. What is the new decibel level?

A) 50 dB
B) 47 dB
C) 53 dB
D) 100 dB

Question 57

A Doppler red shift indicates

A) a shift toward lower frequencies.
B) a shift toward longer wavelengths.
C) that a light source is receding relative to the observer.
D) all of these.

Question 58

If a sound level increases by 40 dB, the intensity increases by a factor of ______________.

A) one hundred thousand
B) ten thousand
C) one thousand
D) one million

Question 59

The intensity of a 80-dB whistle is quadrupled. What is the new decibel level?

A) 80 dB
B) 68 dB
C) 89 dB
D) 320 dB

Question 60

The Doppler effect is observed only when

A) the source of a wave moves toward a stationary observer.
B) there is relative motion between the source of a wave and an observer.
C) an observer moves toward the stationary source of a wave.
D) both the source of a wave and an observer are moving toward each other.

Question 61

The audible range of sound is from 20 Hz to ______________ kHz.

Question 62

When an oscillator is driven in resonance,

A) there are no standing waves.
B) any driving frequency may be used.
C) all natural frequencies are present.
D) there is maximum energy transfer.

Question 63

The SI unit of frequency is ______________.

Question 64

The relationship of wave speed, wavelength, and frequency is given by ______________.

Question 65

Light in a vacuum has a speed of ______________ m/s.

Question 66

What is the frequency, in hertz, of a sound wave (v = 340 m/s) with a wavelength of 68 m?

A) 5 Hz
B) 23120 Hz
C) 340 Hz
D) 0.2 Hz

Question 67

A wave in which the particle displacement is perpendicular to the wave motion is called a(n) ______________ wave.

Question 68

Of the two main types of waves, light is a(n) ______________ wave.

Question 69

The minimum sound intensity that can be detected by the human ear is called the ______________ of hearing.

Question 70

All waves transfer ______________.

Question 71

A wave with a frequency of 5 Hz will have a period of ______________ s.

Question 72

If the wave frequency is doubled, the period of the wave is ______________.

Question 73

A stretched string can have ______________ natural frequency(ies).

A) one
B) 10 times its length in
C) 5 times its length in
D) many

Question 74

What is the wavelength in meters, of a sound wave (v = 340 m/s) with a frequency of 4 Hz?

A) 85 Hz
B) 1360 Hz
C) 340 Hz
D) 0.012 Hz

Question 75

A wave in which the particle displacement is parallel to the wave motion is called a(n) ______________ wave.

Question 76

For a wave with a constant speed, the smaller the period, the ______________ its wavelength.

Question 77

For a wave with a constant speed, the greater the frequency of the wave, the ______________ its wavelength.

Question 78

A wave is a propagation of ______________.

Question 79

A sound with a frequency of 15 Hz is in the ______________ region of the sound spectrum.

Question 80

The frequency and the wavelength of a wave are ______________ proportional.