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Homework Help: Doppler Effect of a car

  1. Mar 10, 2009 #1
    1. The problem statement, all variables and given/known data
    A car is driving down the road at 25m/s. Inside the car, the radio is blaring music at 1800Hz. How would it sound to a person standing still a) in front of the car b) behind the car?


    2. Relevant equations
    [fo/(vw+vo)] = [fs/(vw-vs)]


    3. The attempt at a solution
    a)
    [fo/(vw+vo)] = [fs/(vw-vs)]
    = [fo/350] = [1800/(350-25)]
    = fo = 1938.5Hz

    b)
    [fo/(vw+vo)] = [fs/(vw-vs)]
    = [fo/350] = [1800/(350+25)]
    = fo = 1680Hz
     
    Last edited: Mar 10, 2009
  2. jcsd
  3. Mar 11, 2009 #2

    Kurdt

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    Staff Emeritus
    Science Advisor
    Gold Member

    Re: Waves

    That looks fine for sound travelling at 350m/s.
     
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