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Homework Help: Doppler effect and velocity

  1. Aug 17, 2008 #1
    1. The problem statement, all variables and given/known data

    Speed of sound in air is 340m/s. Sound from a jet, moving a 100m/s through the air, will have a speed of:

    2. Relevant equations

    Doppler effect, and v = Sqrt(bulk/density)

    3. The attempt at a solution

    The answer for this is 340m/s. I was wondering why. Because all the book states is that wave velocity is INDEPENDENT of medium (I thought velocity of a wave was medium dependent).
    Last edited: Aug 17, 2008
  2. jcsd
  3. Aug 17, 2008 #2

    Doc Al

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    Staff: Mentor

    The velocity of sound is 340 m/s with respect to the medium (air). The point of the exercise is that the speed of the source (the jet) is irrelevant.
    That's a pretty wild statement. You're right, the speed of sound most definitely depends on the medium. (What book is that, by the way?) What was the context of that statement?
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