The changing frequency of sound from a train going past your stopped car occurs because of changes in the sound's
A) intensity.
B) timbre.
C) decibels.
D) pitch.

Question

Quizplus · Accepted Answer

The changing frequency of sound from a train going past your stopped car occurs because of changes in the sound's pitch. This is due to the Doppler Effect, which occurs when objects are in motion relative to each other, causing a shift in the frequency of sound waves. As the train moves towards the stationary car, the sound waves are compressed, creating a higher frequency or pitch. As the train moves away from the car, the sound waves are stretched, creating a lower frequency or pitch.

The Changing Frequency of Sound from a Train Going Past