Question 1

Consider two pipes of the same length: one pipe is open at both ends and the other pipe is closed on one end but open at the other end.If the fundamental frequency of the totally open pipe is 300 Hz,what is the fundamental frequency of the other pipe?

Accepted Answer

A)  150 Hz
B)  300 Hz
C)  450 Hz
D)  600 HzE) None of the above
F) All of the above

Question 2

A string of length L is under tension,and the speed of a wave in the string is v.What will be the speed of a wave in the string if the length is increased to 2L but with no change in the mass or tension?

Accepted Answer

A)  v/2
B)  v/ 
C)  v 
D)  2v
E)  4vF) A) and E)
G) A) and D)

Question 3

By how many decibels does the intensity level of a sound increase when you triple the intensity of a source of sound?

Accepted Answer

A)  9.5 dB
B)  4.8 dB
C)  6.0 dB
D)  3.0 dB
E)  12 dBF) All of the above
G) B) and D)

Question 4

The intensity at a distance of 6.0 m from a source that is radiating equally in all directions is 6.0 × 10-10 W/m2.What is the intensity level in dB? The threshold of human hearing is 1.0 × 10-12 W/m2.

Accepted Answer

A)  18 dB
B)  23 dB
C)  28 dB
D)  32 dBE) A) and B)
F) C) and D)

Question 5

Two in-phase loudspeakers that emit sound with the same frequency are placed along a wall and are separated by a distance of 5.00 m.A person is standing 12.0 m away from the wall,equidistant from the loudspeakers.When the person moves 1.00 m parallel to the wall,she experiences destructive interference for the first time.What is the frequency of the sound? The speed of sound in air is 343 m/s.

Accepted Answer

A)  211 Hz
B)  256 Hz
C)  422 Hz
D)  512 Hz
E)  674 HzF) B) and C)
G) A) and C)

Question 6

Calculate the light intensity 1.45 m from a light bulb that radiates 100 W equally in all directions.

Accepted Answer

A)  3.78 W/m2
B)  4.36 W/m2
C)  47.6 W/m2
D)  54.7 W/m2E) C) and D)
F) A) and D)

Question 7

Transverse waves travel at 
In a string that is subjected to a tension of 
If the string is 
Long,what is its mass?

Accepted Answer

A)  0.515 kg
B)  0.216 kg
C)  0.366 kg
D)  0.597 kgE) A) and B)
F) B) and C)

Question 8

What is the intensity of a 70-dB sound? The threshold of human hearing is 1.0 × 10-12 W/m2.

Accepted Answer

A)  10-4 W/m2
B)  10-5 W/m2
C)  10-6 W/m2
D)  10-7 W/m2E) B) and D)
F) All of the above

Question 9

If the intensity level of one trombone is 70 dB,calculate a reasonable estimate for the intensity level of 76 trombones all playing simultaneously in the same place?

Accepted Answer

A)  146 dB
B)  89 dB
C)  70 dB
D)  76 dB
E)  82 dBF) B) and E)
G) A) and E)

Question 10

A siren emitting sound of frequency 1000 Hz approaches a stationary observer at one-half the speed of sound.The observer hears a frequency of

Accepted Answer

A)  1000 Hz
B)  2000 Hz.
C)  500 Hz.
D)  1500 Hz.
E)  none of the above.F) B) and E)
G) None of the above

Question 11

Two in-phase loudspeakers are some distance apart.They emit sound with a frequency of 536 Hz.A microphone is moved between the speakers along the line joining the two speakers with a constant speed of 1.60 m/s.What beat frequency is observed? The speed of sound in air is 343 m/s.

Accepted Answer

A)  5.00 Hz
B)  6.00 Hz
C)  7.00 Hz
D)  8.00 Hz
E)  9.00 HzF) A) and E)
G) None of the above

Question 12

A 15-m rope is pulled taut with a tension of 140 N.It takes 0.545 s for a wave to propagate along the rope.What is the mass of the rope?

Accepted Answer

A)  1.7 kg
B)  2.1 kg
C)  2.8 kg
D)  5.1 kg
E)  3.2 kgF) B) and D)
G) B) and E)

Question 13

Why does the intensity of waves from a small source decrease with the square of the distance from the source?

Accepted Answer

A)  The waves run out of energy as they travel.
B)  The waves spread out as they travel.
C)  The medium through which the waves travel absorbs the energy of the waves.
D)  The waves slow down as they travel away from the source.
E)  The frequency of the waves decreases as they get farther from the source.F) All of the above
G) None of the above

Question 14

In a resonating pipe that is open at one end and closed at the other end,there

Accepted Answer

A)  are displacement nodes at each end.
B)  are displacement antinodes at each end.
C)  is a displacement node at the open end and a displacement antinode at the closed end.
D)  is a displacement node at the closed end and a displacement antinode at the open end.E) All of the above
F) C) and D)

Question 15

You double your distance from a sound source that is radiating equally in all directions.What happens to the intensity level of the sound? It drops by

Accepted Answer

A)  2 dB.
B)  3 dB.
C)  6 dB.
D)  8 dB.E) A) and D)
F) A) and C)

Question 16

A string that is 2.0 meters long is fixed at both ends and tightened until the wave speed is 
What is the frequency of the standing wave shown in the figure?

Accepted Answer

A)  27 Hz
B)  54 Hz
C)  81 Hz
D)  110 HzE) None of the above
F) B) and D)

Question 17

A crane lifts a 2500-kg beam at a steady rate of 15 cm/s using a steel cable whose mass per unit length is 0.65 kg/m.What is the speed of transverse waves on this cable?

Accepted Answer

A)  230 m/s
B)  580 m/s
C)  1200 m/s
D)  1900 m/s
E)  190 m/sF) B) and E)
G) All of the above

Question 18

The sound from the whistle of a truck moving at 17.0 m/s toward a cliff reflects from the cliff and is heard by the driver of the truck.When it is parked at the side of the road,the whistle from the truck produces sound of frequency 2.267 kHz.As observed by the driver of the truck,what is the change in frequency the sound from the whistle due to the reflection? The speed of sound is 343 m/s.

Accepted Answer

A)  236 Hz
B)  228 Hz
C)  207 Hz
D)  118 Hz
E)  472 HzF) D) and E)
G) B) and D)

Question 19

What is the length of the shortest pipe closed on one end and open at the other end that will have a fundamental frequency of 0.060 kHz on a day when the speed of sound is 340 m/s?

Accepted Answer

A)  1.24 m
B)  1.42 m
C)  2.14 m
D)  4.12 mE) A) and C)
F) A) and D)

Question 20

Two loudspeakers placed 6.00 m apart are driven in phase by an audio oscillator having a frequency range from 1595 Hz to 2158 Hz.A point P is located 4.70 m from one loudspeaker and 3.60 m from the other speaker.The speed of sound in the room is 344 m/s.At what frequency (or frequencies) of the oscillator does the sound reaching point P interfere destructively? (There could be more than one correct choice. )

Accepted Answer

A)  2030 Hz
B)  2130 Hz
C)  2100 Hz
D)  1720 Hz
E)  1630 HzF) A) and E)
G) A) and D)

Exam 14: Waves and Sound

Transverse waves travel at In a string that is subjected to a tension of If the string is Long,what is its mass?

Correct Answer
verified

A string that is 2.0 meters long is fixed at both ends and tightened until the wave speed is What is the frequency of the standing wave shown in the figure?

Correct Answer
verified

Consider two pipes of the same length: one pipe is open at both ends and the other pipe is closed on one end but open at the other end.If the fundamental frequency of the totally open pipe is 300 Hz,what is the fundamental frequency of the other pipe?

Correct Answer
verified

What is the length of the shortest pipe closed on one end and open at the other end that will have a fundamental frequency of 0.060 kHz on a day when the speed of sound is 340 m/s?

Correct Answer
verified

Calculate the light intensity 1.45 m from a light bulb that radiates 100 W equally in all directions.

Correct Answer
verified

A 15-m rope is pulled taut with a tension of 140 N.It takes 0.545 s for a wave to propagate along the rope.What is the mass of the rope?

Correct Answer
verified

Correct Answer
verified

If the intensity level of one trombone is 70 dB,calculate a reasonable estimate for the intensity level of 76 trombones all playing simultaneously in the same place?

Correct Answer
verified

Two in-phase loudspeakers are some distance apart.They emit sound with a frequency of 536 Hz.A microphone is moved between the speakers along the line joining the two speakers with a constant speed of 1.60 m/s.What beat frequency is observed? The speed of sound in air is 343 m/s.

Correct Answer
verified

In a resonating pipe that is open at one end and closed at the other end,there

Correct Answer
verified

Why does the intensity of waves from a small source decrease with the square of the distance from the source?

Correct Answer
verified

By how many decibels does the intensity level of a sound increase when you triple the intensity of a source of sound?

Correct Answer
verified

The intensity at a distance of 6.0 m from a source that is radiating equally in all directions is 6.0 × 10^-10 W/m².What is the intensity level in dB? The threshold of human hearing is 1.0 × 10^-12 W/m².

Correct Answer
verified

A siren emitting sound of frequency 1000 Hz approaches a stationary observer at one-half the speed of sound.The observer hears a frequency of

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

You double your distance from a sound source that is radiating equally in all directions.What happens to the intensity level of the sound? It drops by

Correct Answer
verified

A crane lifts a 2500-kg beam at a steady rate of 15 cm/s using a steel cable whose mass per unit length is 0.65 kg/m.What is the speed of transverse waves on this cable?

Correct Answer
verified

A string of length L is under tension,and the speed of a wave in the string is v.What will be the speed of a wave in the string if the length is increased to 2L but with no change in the mass or tension?

Correct Answer
verified

What is the intensity of a 70-dB sound? The threshold of human hearing is 1.0 × 10^-12 W/m².

Correct Answer
verified

Exam 14: Waves and Sound

Transverse waves travel at In a string that is subjected to a tension of If the string is Long,what is its mass?

Correct AnswerverifiedShow Answer

A string that is 2.0 meters long is fixed at both ends and tightened until the wave speed is What is the frequency of the standing wave shown in the figure?

Correct AnswerverifiedShow Answer

Consider two pipes of the same length: one pipe is open at both ends and the other pipe is closed on one end but open at the other end.If the fundamental frequency of the totally open pipe is 300 Hz,what is the fundamental frequency of the other pipe?

Correct AnswerverifiedShow Answer

What is the length of the shortest pipe closed on one end and open at the other end that will have a fundamental frequency of 0.060 kHz on a day when the speed of sound is 340 m/s?

Correct AnswerverifiedShow Answer

Calculate the light intensity 1.45 m from a light bulb that radiates 100 W equally in all directions.

Correct AnswerverifiedShow Answer

A 15-m rope is pulled taut with a tension of 140 N.It takes 0.545 s for a wave to propagate along the rope.What is the mass of the rope?

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

If the intensity level of one trombone is 70 dB,calculate a reasonable estimate for the intensity level of 76 trombones all playing simultaneously in the same place?

Correct AnswerverifiedShow Answer

Two in-phase loudspeakers are some distance apart.They emit sound with a frequency of 536 Hz.A microphone is moved between the speakers along the line joining the two speakers with a constant speed of 1.60 m/s.What beat frequency is observed? The speed of sound in air is 343 m/s.

Correct AnswerverifiedShow Answer

In a resonating pipe that is open at one end and closed at the other end,there

Correct AnswerverifiedShow Answer

Why does the intensity of waves from a small source decrease with the square of the distance from the source?

Correct AnswerverifiedShow Answer

By how many decibels does the intensity level of a sound increase when you triple the intensity of a source of sound?

Correct AnswerverifiedShow Answer

The intensity at a distance of 6.0 m from a source that is radiating equally in all directions is 6.0 × 10-10 W/m2.What is the intensity level in dB? The threshold of human hearing is 1.0 × 10-12 W/m2.

Correct AnswerverifiedShow Answer

A siren emitting sound of frequency 1000 Hz approaches a stationary observer at one-half the speed of sound.The observer hears a frequency of

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

You double your distance from a sound source that is radiating equally in all directions.What happens to the intensity level of the sound? It drops by

Correct AnswerverifiedShow Answer

A crane lifts a 2500-kg beam at a steady rate of 15 cm/s using a steel cable whose mass per unit length is 0.65 kg/m.What is the speed of transverse waves on this cable?

Correct AnswerverifiedShow Answer

A string of length L is under tension,and the speed of a wave in the string is v.What will be the speed of a wave in the string if the length is increased to 2L but with no change in the mass or tension?

Correct AnswerverifiedShow Answer

What is the intensity of a 70-dB sound? The threshold of human hearing is 1.0 × 10-12 W/m2.

Correct AnswerverifiedShow Answer

Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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The intensity at a distance of 6.0 m from a source that is radiating equally in all directions is 6.0 × 10^-10 W/m².What is the intensity level in dB? The threshold of human hearing is 1.0 × 10^-12 W/m².

Correct Answer
verified

Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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What is the intensity of a 70-dB sound? The threshold of human hearing is 1.0 × 10^-12 W/m².

Correct Answer
verified