Mini-Quiz: Derivation of Doppler Effect Velocity Equations

1. How do you find the velocity for a moving source and stationary observer?

   Take the general equation, set vS = 0, and solve for vSSorry, not correct. Try another button. Take the general equation, set vO = 0, and solve for vSThat is correct. You know about velocity and the Doppler Effect. Take the general equation, set vO = 0, and solve for vOGood try, but not right. Select another answer.

2. What is the velocity with respect to frequency for a moving observer and stationary source?

   vS = − cΔf/fOOops! Wrong answer. Re-read the question and try again. vO = −cΔλ/λOSorry, not correct. Try another button. vO = cΔf/fSCorrect. You are doing great!

3. Why is -c used for the wave velocity after it is reflected off a moving object?

   The wave is going in the opposite direction of the x-axisThat is correct. You know about velocity and the Doppler Effect. The velocity of the object is subtracted from the wave velocityGood try, but not right. Select another answer. It is one of the mysteries of the Doppler EffectOops! Wrong answer. Re-read the question and try again.

Pick an answer to see instant feedback. Re-read the lesson if you miss one.