Light from a stationary spaceship is observed, then the spaceship moves directly away from the observer at high speed.As a result, the light seen by the observer has:
A)a higher frequency and a longer wavelength than before
B)a lower frequency and a shorter wavelength than before
C)a higher frequency and a shorter wavelength than before
D)a lower frequency and a longer wavelength than before
E)the same frequency and wavelength as before

Question

Quizplus · Accepted Answer

This is a question about the Doppler effect, where the motion of the source of waves relative to an observer affects the frequency and wavelength of the waves. When the spaceship moves away from the observer, the light waves it emits are stretched out, increasing their wavelength and decreasing their frequency. As a result, the observer sees light with a lower frequency and longer wavelength than before, which is option D.

Light from a Stationary Spaceship Is Observed, Then the Spaceship