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Homework Help: Properties of Rifle Sound

  1. Mar 15, 2007 #1

    tdk

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    1. The problem statement, all variables and given/known data

    "A rifle is fired in a valley with parallel vertical walls. The echo from one wall is heard 2.0 s after the rifle was fired. The echo from the other wall is heard 2.0 s after the first echo. How wide is the valley?

    2. Relevant equations

    I dont know any relevant equations. v=wavelength x frequency? Do I have to convert something into decibels?

    3. The attempt at a solution

    time=2 s
    distance=?
    .
     
    Last edited by a moderator: Mar 16, 2007
  2. jcsd
  3. Mar 15, 2007 #2
    No nothing that cpplex--just that the speed of sound is 340meters/sec. Hint: to avoid simple errors, draw a picture of the reflecting sound waves so as to include all the distances.
     
  4. Mar 15, 2007 #3

    tdk

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    But I dont understand how you apply the speed of sound to the problem. Do you multiply it by 2?.
     
    Last edited by a moderator: Mar 16, 2007
  5. Mar 15, 2007 #4
    know leave the speed alone and as i suggested draw a diagram. In this case, try to isolate the time requires for sound to span the valley. Hint its 1/2 the sum...
     
  6. Mar 15, 2007 #5

    tdk

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    alright pugfug, I told you I unclicked the "Automatically parse links in text" and thats why the link wasnt clickable anymore. And now everytime I post I unclick it so it doesnt come up as a link. Do you understand that? I dont get why I cant post here if the link isnt even clickable, whats the harm?

    Thanks Denverdoc I'll try that.
     
    Last edited by a moderator: Mar 16, 2007
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