Deck 5: Wave Motions and Sound

Question 1

Longitudinal waves with a frequency above 20,000 Hz are

A)impossible.
B)supersonic.
C)ultrasonic.
D)infrasonic.

Answer 1

C

Question 2

The amplitude of a wave is the distance from the crest to the equilibrium position.

Answer 2

True

Question 3

The fundamental frequency of a vibrating string has a length that is 1/2 the wavelength.

Answer 3

True

Question 4

In longitudinal waves, the medium

A)vibrates in a direction perpendicular to the direction of motion of the wave.
B)vibrates in the same direction the wave is moving.
C)moves in sort of a circular motion.
D)doesn't vibrate; the disturbance just moves through the medium.

Question 5

Through which medium will sound travel most rapidly?

A)vacuum
B)air
C)water
D)steel

Question 6

When you are moving toward a stationary source of a sound, its frequency will appear lower than it actually is.

Question 7

Sound travels faster through cold, denser air than through warm, less dense air.

Question 8

The higher the frequency of a sound wave

A)the higher the pitch.
B)the longer the wavelength.
C)the higher the velocity.
D)the greater the amplitude.

Question 9

The characteristic of a sound wave that you interpret as loudness is related to

A)frequency.
B)wavelength.
C)amplitude.
D)velocity.

Question 10

Waves that move through air are transverse.

Question 11

If v = $\lambda$ f, then how are $\lambda$ and f related?

A) $\lambda$ is directly proportional to f
B) $\lambda$ is inversely proportional to f
C) $\lambda$ is a factor of f
D) $\lambda$ and f are unrelated

Question 12

Reflected sound waves that are heard within 0.1 s

A)undergo a gain in volume.
B)make an echo.
C)cause interference.
D)make a beat.

Question 13

The frequency is the time required for one complete cycle.

Question 14

The time that is required for a vibrating object to complete one full cycle is called

A)frequency.
B)wavelength.
C)amplitude.
D)period.

Question 15

A sound of 20 dB intensity is twice as loud as one of 10 dB.

Question 16

In resonance the amplitude of a vibrating source becomes larger.

Question 17

Sound waves in air

A)are longitudinal waves.
B)are produced by something vibrating.
C)undergo refraction when they pass through warm and cold air.
D)All of the above.

Question 18

The restoring force of a spring is proportional to the displacement of the object at the end.

Question 19

Transverse mechanical waves can pass through

A)solids.
B)liquids.
C)gases.
D)All of the above.

Question 20

Piano tuners listen to the beat frequency between their tuning fork and the wire they are tuning.

Question 21

A sound that is perceived as twice as loud requires

A)twice the intensity.
B)four times the intensity.
C)ten times the intensity.
D)one-hundred times the intensity.

Question 22

When the trough of one wave arrives at the same time and place as the crest of an otherwise identical wave,

A)constructive interference occurs.
B)destructive interference occurs.
C)resonance occurs.
D)they don't interact with each other.

Question 23

You are able to hear sounds from farther away on a cool night because sound waves are refracted toward

A)cooler air near the ground.
B)warmer air above the ground.
C)cooler air above the ground.
D)warmer air near the ground.

Question 24

A noise level of 65 decibels is measured for

A)a whisper.
B)a jet plane.
C)normal conversation.
D)a library.

Question 25

The lowest frequency possible in a vibrating string undergoing resonance is

A)the fundamental frequency.
B)determines the pitch of the musical note sounded.
C)has one antinode.
D)All of the above.

Question 26

What is the range of normal human hearing?

A)200 to 120,000 Hz
B)20 to 2,000 Hz
C)50 to 10,000 Hz
D)20 to 20,000 Hz

Question 27

Condensation in a longitudinal wave corresponds to what part of a transverse wave?

A)crest
B)trough
C)wavelength
D)amplitude

Question 28

Resonance occurs at a (an)

A)natural frequency.
B)intensity match.
C)point of constructive interference.
D)point of destructive interference.

Question 29

Suppose that you hold a vibrating 340-Hz tuning fork near a guitar string that is vibrating at 350 Hz.What you hear is

A)two separate tones of different frequency.
B)one tone with a frequency of 345 Hz.
C)beats with a frequency of 10 Hz.
D)one tone with a frequency of 690 Hz.

Question 30

The bending of a wave at the boundary between two media is called

A)reflection.
B)resonance.
C)reverberation.
D)refraction.