Mini-Quiz: Doppler Effect Equations for Light

1. What is the red-shift frequency equation?

   fr = f(1 − vr/c)That is correct. You understand the Doppler effect. fr = f(1 + vr/c)Sorry, not correct. Try another button. fr = f(1 − c/vr)Good try, but not right. Select another answer.

2. If the velocity of an object towards you increases, what happens to the wavelength of the light?

   It turns blueSorry, not correct. Try another button. No change is noticedOops! Wrong answer. Re-read the question and try again. The wavelength is less than the original spectral lineCorrect. You know your equations!

3. If the observed wavelength λr equals the emitted wavelength, what is vr?

   cOops! Wrong answer. Re-read the question and try again. c/2Good try, but not right. Select another answer. 0That is correct. You understand the Doppler effect.

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