The Doppler effect refers to changes in a sound wave's
A) frequency caused by motion of a source or receiver.
B) frequency caused by a change in speed of sound.
C) amplitude caused by motion of a source or receiver.
D) amplitude caused by a change in speed of sound.

Question

Quizplus · Accepted Answer

The Doppler effect refers to changes in frequency caused by motion of a source or receiver. It is the reason why a siren sounds higher-pitched when the ambulance is approaching and lower-pitched when it is moving away. The Doppler effect has nothing to do with changes in amplitude caused by motion or changes in the speed of sound.

The Doppler Effect Refers to Changes in a Sound Wave's