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• ### Sound waves

are longitudinal waves.

### The through of the sine curve used to represent a sound wave corresponds to

a rarefaction.

compression

frequency

### Of the following materials, sound waves travel fastest through

steel at 0 degrees Celsius.

### In general, sound travels faster through

solids than through gases.

### The distance between wave fronts of plane waves corresponds to ___ of a sound wave.

one wavelength

### A train moves down the track towards an observer. The sound from the train, as heard by the observer, is ___ the sound heard by a passenger on the train.

higher in pitch than

all waves.

### The property of sound called intensity is proportional to the rate at which energy flows through

an area perpendicular to the direction of propagation.

one-ninth

power.

by 20 units.

decibels.

resonance

### The Tacoma Narrows bridge collapsed in 1940 when winds caused ___ to build up in the bridge.

a standing wave

### For a standing wave in an air column in a pipe that is open at both ends, there must be at least

two antinodes and one node.

### When an air column vibrates in a pipe that is open at both ends,

all harmonics are present.

### When an air column vibrates in a pipe that is closed at one end,

only odd harmonics are present.

1000 Hz

2L.

harmonics.

3 Hz

495 Hz

### Audible beats are formed by the interference of two waves

of slightly different frequencies.

4 Hz

plane waves.

### If you are on a train, how will the pitch of the train's whistle sound to you as the train moves?

The pitch will not change.

70 dB

8 Hz

416 Hz

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