Sound Waves

Front

How is a sound wave different from a light wave?

Back

A sound wave is not capable of traveling through a vacuum.

Front

How many times more intense is normal conversation (60 dB) compared to a mosquito's buzz (40 dB)?

Back

100

Front

How many IPods are needed to produce the same intensity as 120 dB if one IPod produces 100 dB?

Back

100

Front

An automatic focus camera uses ultrasonic sound waves to determine the distance of an object. If a sound wave (speed = 340 m/s) returns to the camera 0.150 seconds after leaving, how far away is the object?

Back

25.5 m

Front

Frequency of sound wave produced by mosquito's wing beats at 600 beats per second.

Back

600 Hz

Front

Doubling the frequency of a wave source ________ the speed of the waves.

Back

halves

Front

Playing middle C on the piano keyboard produces a sound with a frequency of 256 Hz. Assuming the speed of sound in air is 345 m/s, determine the wavelength of the sound corresponding to the note of middle C.

Back

1.35 meters

Front

Two sound waves are traveling through a container of unknown gas. Wave A has a wavelength of 1.2 m. Wave B has a wavelength of 3.6 m. The velocity of wave B must be __________ the velocity of wave A. Options: one-ninth, one-third, the same as, three times larger than.

Back

the same as

Answer explanation

The speed of a wave does not depend upon its wavelength, but rather upon the properties of the medium. The medium has not changed, so neither has the speed.

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Front

Why do sound waves create regions of high and low pressure?

Back

Sound vibrates longitudinally; the longitudinal movement of air produces pressure fluctuations.

Front

A musical note that is separated by an octave from middle C (256 Hz) has a frequency of _____.

Back

128 Hz