The car in the drawing is moving to the left at 35 m/s. The car's horn continuously emits a 2.20 × 102 Hz sound. The figure also shows the first two regions of compression of the emitted sound waves. The speed of sound is 343 m/s.
-How far has the initial compression traveled when the second compression is emitted?
A)0.77 m
B)1.56 m
C)7.7 m
D)15.5 m
E)35 m

Question

The car in the drawing is moving to the left at 35 m/s. The car's horn continuously emits a 2.20 × 102 Hz sound. The figure also shows the first two regions of compression of the emitted sound waves. The speed of sound is 343 m/s. 
-How far has the initial compression traveled when the second compression is emitted?
A)0.77 m 
B)1.56 m 
C)7.7 m 
D)15.5 m 
E)35 m

Quizplus · Accepted Answer

The distance between two consecutive compressions of the sound wave is given by:
distance = wavelength = speed of sound / frequency
distance = 343 m/s / 220 Hz = 1.56 m
Therefore, the initial compression has traveled a distance of 1.56 m when the second compression is emitted.

The Car in the Drawing Is Moving to the Left