The reason that you do not observe a Doppler shift when you listen to the car radio while driving is that
A) the source and observer are moving at the same speed.
B) the air inside the car is moving at the same speed as the car.
C) the speed of the car is too slow compared to the speed of sound.
D) the speed of the car is too fast compared to the speed of sound.
E) there is a Doppler shift but we don't notice it.

Question

Quizplus · Accepted Answer

The Doppler effect is observed when there is relative motion between the source of the sound waves and the observer. In the case of listening to the car radio while driving, the car and the radio station are both moving at the same speed relative to each other, so there is no relative motion and therefore no Doppler shift.

The Reason That You Do Not Observe a Doppler Shift