The difference between lightwaves approaching and lightwaves receding is
A)when approaching,lightwaves have higher frequency; when receding their frequency is lower.
B)when approaching,lightwaves have lower frequency; when receding their frequency is higher.
C)the frequency of approaching lightwaves remain constant,while receding lightwaves are invisible.
D)There is no difference

Question

Quizplus · Accepted Answer

This phenomenon is known as the Doppler effect, which describes the change in frequency of a wave (in this case light waves) due to the relative motion between the source of the wave and the observer. When the source of light approaches the observer, the light waves are compressed, resulting in higher frequency. On the other hand, when the source of light recedes from the observer, the light waves are stretched, resulting in lower frequency. Therefore, choice A is the correct answer.

The Difference Between Lightwaves Approaching and Lightwaves Receding Is