If the speed of a continuous wave is constant, as you increase the frequency of the wave, the wave must have a proportionally _________ wavelength
Fill in the blank(s) with correct word
Question 2
As you increase in altitude in the atmosphere, the speed of sound _________.
Fill in the blank(s) with correct word
Question 3
Combining two sounds of equal intensity will give a sound level __________ higher than the sound level due to just one of them.
Fill in the blank(s) with correct word
Question 4
A sound level of 80 dB has __________ times the amplitude of a 60 dB sound.
Fill in the blank(s) with correct word
Question 5
The only way to make sound travel faster in air is to change the air's ____________.
Fill in the blank(s) with correct word
Question 6
The wavelength of ultrasound at 1 million Hz in air where the speed of sound is 340 m/s is __________.
Fill in the blank(s) with correct word
Question 7
Two uses of ultrasound are __________ and __________.
Fill in the blank(s) with correct word
Question 8
In ultrasound the __________ of the sound is much greater than in normal sound.
Fill in the blank(s) with correct word
Question 9
As you move farther away from a source emitting a pure tone, the __________ of the sound you hear decreases.
Fill in the blank(s) with correct word
Question 10
When two identical waves undergo _______________ interference, the net amplitude is zero.
Fill in the blank(s) with correct word
Question 11
Two speakers in a stereo emit identical pure tones. As you move around in front of the speakers, you hear the sound alternating between loud and zero. This occurs because of __________.
Fill in the blank(s) with correct word
Question 12
You can hear sound through an open window from sources that are not in your line of sight because of __________.
Fill in the blank(s) with correct word
Question 13
You shout at a cliff, and hear your echo in 2 seconds. If the speed of sound in the air is 340 m/s, the distance of the cliff from you is __________.
Fill in the blank(s) with correct word
Question 14
Increasing the speed of waves on a guitar string increases the _________ of the sound it produces.
Fill in the blank(s) with correct word
Question 15
A wave moves in a rope with a certain wavelength. A second wave is made to move in the same rope with twice the wavelength of the first wave. The frequency of the second wave is _________ times the frequency of the first wave.
Fill in the blank(s) with correct word
Question 16
Two examples of a transverse wave are __________ and __________.
Fill in the blank(s) with correct word
Question 17
Two examples of a longitudinal wave are __________ and __________.
Fill in the blank(s) with correct word
Question 18
The wavelength of a wave multiplied by the frequency of the wave is the wave's __________.
Fill in the blank(s) with correct word
Question 19
A _________ wave is one with its oscillations perpendicular to the direction of propagation.
Fill in the blank(s) with correct word
Question 20
The maximum displacement of points on a wave from the equilibrium position is the wave's __________.
Fill in the blank(s) with correct word
Question 21
The distance between two successive like' points on a wave is the wave's __________.
Fill in the blank(s) with correct word
Question 22
A complex tone can be produced by combining two or more __________.
Fill in the blank(s) with correct word
Question 23
The number of cycles of a wave passing a point per unit time is the wave's __________.
Fill in the blank(s) with correct word
Question 24
You put one ear on a steel railroad track while your friend a distance of 400 m away taps on the rail with a stone. You will hear the sound through the steel rail in _________ and through the air where the speed of sound is 344 m/s in _______.
a. 0.08 s b. 0.5 s
c. 1.2 s d. 2.4 s
Question 25
In order for two waves to interfere completely destructively, they must
a. have the same amplitude.
b. be exactly out of phase.
c. one wave's peak must align with the other's valley.
d. be transverse waves.
e. all of the above
Question 26
In a plane wave, the wavefronts are
a. circular.
b. flat.
c. parallel.
d. perpendicular to the direction of propagation.
Question 27
An example of a longitudinal wave is
a. a sound wave in air.
b. a wave on a rope.
c. a water wave.
d. a sound wave in a metal bar.
e. none of the above.
Question 28
An example of a transverse wave is a
a. sound wave in air.
b. wave on a rope.
c. water wave.
d. sound wave in a metal bar.
e. none of the above
Question 29
Sound waves propagate in
a. one dimension. b. two dimensions.
c. three dimensions. d. four dimensions.
Question 30
You are on a boat in a fog and know there are cliffs ahead of you somewhere, but you cannot see them. You use your fog horn to send out a blast of sound (assume the temperature of the air is 20 oC) and the time it takes for the sound to return to you is 20.0 s. How far away are the cliffs (in metric units)? Hint: Be careful and think about the physics of the problem. You may want to make a sketch of the situation to help you determine the answer.
a. 1798 m b. 3444 m
c. 3596 m d. 7192 m
Question 31
You are on an island where a huge explosion at a distance of 500 miles away can be heard. How long (in seconds) does it take the sound to travel to your location? Assume the temperature of the air is 20 oC.
a. 1.4 s b. 5.6 s
c. 2340 s d. 8955 s
Question 32
What frequency of sound traveling in air at 40 oC has a wavelength of 0.50 m?
a. 20 Hz b. 344.7 Hz
c. 502.9 Hz d. 711.2 Hz
Question 33
In the upper atmosphere at altitudes where commercial airlines travel, we find extremely cold temperatures. What is the speed of sound (in metric units) for a temperature of 49.0 oC?
a. 984.9 m/s b. 300.8 m/s
c. 344.7 m/s d. 140.7 m/s
Question 34
Harmonics
a. are components of a complex waveform.
b. have frequencies that are integer multiples of the frequency of the complex waveform.
c. are pure tones.
d. have sinusoidal waveforms.
e. all of the above
Question 35
A sound with ten times the amplitude of another sound is judged to be
a. twice as loud. b. ten times as loud.
c. 10 dB higher in sound level. d. 20 dB higher in sound level.
Question 36
If you move twice as far away from a lawn mower running in an open field, the amplitude of the sound you hear will be ___________ what it was before.
a. the same as
b. twice
c. half
d. four times
e. one fourth
Question 37
If one lawn mower causes an 80-dB sound level at a point nearby, four lawnmowers together would cause a sound level of ____________ at that point.
a. 92 dB b. 84 dB
c. 86 dB d. none of the above
Question 38
Combining two sounds of equal intensity will give a sound level ___________ than the sound level due to just one of them.
a. twice as loud b. 3 dB higher
c. 10 dB higher d. 2 dB higher
Question 39
A zero decibel sound level
a. has zero amplitude. b. is nonsense.
c. is just at the threshold of hearing. d. none of the above
Question 40
A sound level of 80 dB has ___________ the amplitude of a 60 dB sound.
a. ten times b. twenty times
c. one tenth d. twice
Question 41
The 3rd harmonic of a complex tone has a frequency of 1,200 Hz. The frequency of the tone is
a. 200 Hz. b. 400 Hz.
c. 600 Hz. d. none of the above.
Question 42
An echo is a sound wave that has been
a. diffracted.
b. refracted.
c. reflected.
d. reverberated.
e. amplified.
Question 43
You see a lightning flash and half a second later hear a loud blast of thunder. How far away did the lightning hit?
a. about a mile b. half a mile
c. a tenth of a mile d. none of the above
Question 44
Doppler radar can
a. catch speeders.
b. measure the speed of a pitcher's fastball.
c. detect tornadoes.
d. do all of the above.
Question 45
You listen to a live orchestra concert from a cheap seat far away, high up in the balcony. The music seems to be a little out of sync with the conductor's beat. Why?
a. The musicians are paying no attention to the conductor.
b. You are noticing a time lag due to the finite speed of sound.
c. The orchestra is not very good.
d. The viola section is dragging.
Question 46
The wavelength of ultrasound at 1 million Hz in air where the speed of sound is 340 m/s is
a. 0.00000034 m.
b. 0.0000034 m.
c. 0.00034 m.
d. 0.34 m.
e. 340,000,000 m.
Question 47
Ultrasound is used
a. to form images of internal organs.
b. by bats to navigate.
c. in automatic focus cameras.
d. to control insects.
e. all of the above
Question 48
In ultrasound the _____________ of the sound is much greater than in normal sound.
a. frequency
b. period
c. wavelength
d. amplitude
e. speed
Question 49
Which of the following is not one of the ways sound can be used?
a. to circulate the refrigerant in a refrigerator
b. to relay information to orbiting satellites
c. to form images of internal organs
d. to measure the air temperature aloft
e. to make a bubble in water produce light
Question 50
Choose the correct statement.
a. The perceived pitch of a sound usually doesn't depend on the sound's frequency.
b. The frequency of each musical note is 10 Hz higher than that of the next lower note.
c. The decibel is the standard measure of tone quality.
d. The perceived loudness of a sound depends somewhat on frequency.
Question 51
As you move farther away from a source emitting a pure tone, the ___________ of the sound you hear decreases.
a. frequency
b. period
c. wavelength
d. amplitude
e. none of the above
Question 52
Two speakers in a stereo emit identical pure tones. As you move around in front of the speakers, you hear the sound alternating between loud and zero. This occurs because of
a. interference.
b. changing sound level.
c. diffraction.
d. the Doppler effect.
e. shock waves.
Question 53
When two identical waves arrive at the same place in phase, there is
a. constructive interference.
b. destructive interference.
c. diffraction.
d. a Doppler effect.
e. a shock wave.
Question 54
Which of these waves will diffract the most when passing through a 20 cm wide opening in a barrier?
a. a wave with a wavelength of 25 cm
b. a wave with a wavelength of 2 cm
c. a wave with a wavelength of 0.05 cm
d. none of these waves will diffract at all
Question 55
You can hear sound through an open window from sources that are not in your line of sight because of
a. interference.
b. diffraction.
c. the sound level.
d. the Doppler effect.
e. none of the above.
Question 56
A source emits sound at a fixed constant frequency f.If the source moves, the wavelength of the sound in front of the direction of motion is ____________ the wavelength behind the direction of motion.
a. the same as b. larger than
c. smaller than d. unrelated to
Question 57
A source emits sound at a fixed constant frequency f.If the source moves away from you faster than the speed of sound in air, the frequency that you hear is
a. the same as f. b. higher than f.
c. lower than f. d. unrelated to f.
Question 58
A source emits sound at a fixed constant frequency f.If the temperature of the air rises, the frequency you hear is
a. the same as f. b. higher than f.
c. lower than f. d. unrelated to f.
Question 59
A source emits sound at a fixed constant frequency f.If the source moves away from you, and at the same time you run away from the source, the frequency you hear is
a. the same as f. b. higher than f.
c. lower than f. d. unrelated to f.
Question 60
A source emits sound at a fixed constant frequency f.If you run towards the source, the frequency you hear is
a. the same as f. b. higher than f.
c. lower than f. d. unrelated to f.
Question 61
A source emits sound at a fixed constant frequency f.If the source moves away from you, the frequency you hear is
a. the same as f. b. higher than f.
c. lower than f. d. unrelated to f.
Question 62
You shout at a cliff, and hear your echo in 2 seconds. If the speed of sound in the air is 340 m/s, the distance of the cliff from you is
a. 85 m.
b. 170 m.
c. 340 m.
d. 680 m.
e. none of the above.
Question 63
A wave moves in a rope with a certain wavelength. A second wave is made to move in the same rope with twice the wavelength of the first wave. The frequency of the second wave is _______________ the frequency of the first wave.
a. 1/2 b. the same as
c. 2 times d. unrelated to
Question 64
Which of the following can change the frequency of a wave?
a. interference
b. the Doppler effect
c. diffraction
d. all of the above
Question 65
Two sound waves traveling through the air have different frequencies. Consequently, they must also have different
a. amplitudes.
b. speeds.
c. wavelengths.
d. all of the above
Question 66
If a source of sound is traveling toward you, the speed of the sound waves reaching you is _______________ the speed the sound waves would have had if the source were stationary.
a. faster than
b. slower than
c. the same as
Question 67
You drop a rock in a pond, and the water waves travel away from the rock with a certain speed. You drop a heavier rock in the water. The speed of the waves in the water from the heavier rock
a. remains unchanged.
b. increases.
c. decreases.
d. cannot be determined.
Question 68
When the frequency of the source of a water wave increases, the speed of the waves traveling in the water
a. remains unchanged.
b. increases.
c. decreases.
d. cannot be determined.
Question 69
When the frequency of the source of a water wave increases, the distance between successive peaks in the wave
a. remains unchanged.
b. increases.
c. decreases.
d. cannot be determined.
Question 70
The wavelength of a wave multiplied by the frequency of the wave is the wave's
a. speed.
b. frequency.
c. wavelength.
d. amplitude.
e. loudness.
Question 71
The distance between peaks on a wave divided by the time for the wave to travel this distance is the wave's
a. speed.
b. frequency.
c. wavelength.
d. amplitude.
e. loudness.
Question 72
The maximum displacement of points on a wave from the equilibrium position is the wave's
a. speed.
b. frequency.
c. wavelength.
d. amplitude.
e. loudness.
Question 73
What is the symbol traditionally used to represent wavelength?
a. wl b. y
c. d.
Question 74
The distance between two successive like' points on a wave is the wave's
a. speed.
b. frequency.
c. wavelength.
d. amplitude.
e. loudness.
Question 75
The number of cycles of a wave passing a point per unit time is the wave's
a. speed.
b. frequency.
c. wavelength.
d. amplitude.
e. loudness.
Question 76
What is meant by a wave medium?
a. a wave of moderate amplitude
b. water
c. air
d. any material through which a wave travels
Question 77
Sound waves propagate in two dimensions.
a. True
b. False
Indicate whether the statement is true or false
Question 78
For waves moving through the atmosphere at a constant velocity, higher frequency waves must have proportionally longer wavelengths.
a. True
b. False
Indicate whether the statement is true or false
Question 79
In the troposphere segment of the Earth's atmosphere, as you increase in altitude the temperature decreases. This means the speed of sound decreases as you increase in altitude.
a. True
b. False
Indicate whether the statement is true or false
Question 80
If you increase the linear mass density of a rope, the speed of a wave on the rope also increases.
a. True
b. False
Indicate whether the statement is true or false
Question 81
Telephones don't transmit frequencies above 3,400 Hz. Musical notes should sound normal over the telephone as long as they are below 3,400 Hz.
a. True
b. False
Indicate whether the statement is true or false
Question 82
Your vocal cords are used to produce all the sounds you make while speaking.
a. True
b. False
Indicate whether the statement is true or false
Question 83
Two identical sound producers will sound twice as loud as just one.
a. True
b. False
Indicate whether the statement is true or false
Question 84
A sound with ten times the amplitude of another sound is judged to be ten times as loud.
a. True
b. False
Indicate whether the statement is true or false
Question 85
Combining two sounds of equal intensity will give a sound level 3 dB higher than the sound level due to just one of them.
a. True
b. False
Indicate whether the statement is true or false
Question 86
A zero decibel sound level has zero amplitude.
a. True
b. False
Indicate whether the statement is true or false
Question 87
A sound level of 80 dB has twenty times the amplitude of a 60 dB sound.
a. True
b. False
Indicate whether the statement is true or false
Question 88
Two uses of ultrasound are navigation by bats and controlling insects.
a. True
b. False
Indicate whether the statement is true or false
Question 89
In ultrasound the wavelength of the sound is much smaller than in normal sound.
a. True
b. False
Indicate whether the statement is true or false
Question 90
Reverberation time of a room can be increased by covering the walls with better reflectors of sound.
a. True
b. False
Indicate whether the statement is true or false
Question 91
Reverberation can both inhibit conversation and enhance music.
a. True
b. False
Indicate whether the statement is true or false
Question 92
As you move farther away from a source emitting a pure tone, the frequency of the sound you hear decreases.
a. True
b. False
Indicate whether the statement is true or false
Question 93
In order for two waves to interfere completely destructively, they must have the same amplitude.
a. True
b. False
Indicate whether the statement is true or false
Question 94
Two speakers in a stereo emit identical pure tones. As you move around in front of the speakers, you hear the sound alternating between loud and zero. This occurs because of diffraction.
a. True
b. False
Indicate whether the statement is true or false
Question 95
When two identical waves arrive at the same place in phase, there is destructive interference.
a. True
b. False
Indicate whether the statement is true or false
Question 96
You can hear sound through an open window from sources that are not in your line of sight because of diffraction.
a. True
b. False
Indicate whether the statement is true or false
Question 97
If the source moves, the wavelength of the sound in front of the direction of motion is smaller than the wavelength behind the direction of motion.
a. True
b. False
Indicate whether the statement is true or false
Question 98
Sound cannot travel through solid steel.
a. True
b. False
Indicate whether the statement is true or false
Question 99
A source emits sound at a fixed constant frequency f.If the source moves away from you faster than the speed of sound in air, you do not hear any frequency but instead a sonic boom.'
a. True
b. False
Indicate whether the statement is true or false
Question 100
A source emits sound at a fixed constant frequency f. If the temperature of the air rises, the frequency you hear is higher than f.
a. True
b. False
Indicate whether the statement is true or false
Question 101
A source emits sound at a fixed constant frequency f.If the source moves away from you, and at the same time you run away from the source, the frequency you hear is the same as f.
a. True
b. False
Indicate whether the statement is true or false
Question 102
A source emits sound at a fixed constant frequency f.If you run towards the source, the frequency you hear is lower than f.
a. True
b. False
Indicate whether the statement is true or false
Question 103
A source emits sound at a fixed constant frequency f.If the source moves away from you, the frequency you hear is lower than f.
a. True
b. False
Indicate whether the statement is true or false
Question 104
A wave moves in a rope with a certain wavelength. A second wave is made to move in the same rope with twice the wavelength of the first wave. The frequency of the second wave is half the frequency of the first wave.
a. True
b. False
Indicate whether the statement is true or false
Question 105
The speed of a wave is the same as the speed of the particles displaced by the wave.
a. True
b. False
Indicate whether the statement is true or false
Question 106
Waves carry energy.
a. True
b. False
Indicate whether the statement is true or false
Question 107
Regions of a longitudinal wave where the particles of the medium are squeezed together are called compressions.
a. True
b. False
Indicate whether the statement is true or false
Question 108
Sound in a vacuum is impossible.
a. True
b. False
Indicate whether the statement is true or false
Question 109
A sound wave in a metal bar is an example of a longitudinal wave.
a. True
b. False
Indicate whether the statement is true or false
Question 110
A water wave is an example of a transverse wave.
a. True
b. False
Indicate whether the statement is true or false
Question 111
When the frequency of the source of a water wave increases, the speed of the waves traveling in the water increases.
a. True
b. False
Indicate whether the statement is true or false
Question 112
When the frequency of the source of a water wave increases, the distance between successive peaks in the wave increases.
a. True
b. False
Indicate whether the statement is true or false
Question 113
The wavelength of a wave divided by the frequency of the wave is the wave's speed.
a. True
b. False
Indicate whether the statement is true or false
Question 114
The maximum displacement of points on a wave from the equilibrium position is the wave's wavelength.
a. True
b. False
Indicate whether the statement is true or false
Question 115
The distance between two successive like' points on a wave is the wave's wavelength.
a. True
b. False
Indicate whether the statement is true or false
Question 116
The number of cycles of a wave passing a point per unit time is the wave's period.
a. True
b. False
Indicate whether the statement is true or false
Question 117
The flash from a camera is an example of a continuous wave.
a. True
b. False
Indicate whether the statement is true or false
Question 118
An aluminum wing on a plane is 38 m long when the temperature is 20 oC. At what temperature (in oC) would the wing be 0.04 m shorter? Enter your answer to one decimal place. You should think about the physics of the situation before trying to solve the problem. (Hint: You are being asked for a temperature, not a temperature change).