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Homework Help: A submarine sonar system sends a burst of sound with a frequency of

  1. Jan 15, 2012 #1

    k0k

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    A submarine sonar system sends a burst of sound with a frequency of 325Hz. The sound wave bounces off an underwater rock face and returns to the submarine in 8.50s. If the wavelength of the sound is 4.71m, how far away is the rock face? (Ans: 6.51km )

    --
    v=fλ

    λ=wavelength
    f=frequency
    v=velocity
    --
    v=fλ
    v=325Hz X 4.71m
    =1530.75m/s

    v=d/t
    d=vt
    = 1530.75m/s X 8.50s
    =13011.375m
    =13011.375m/2
    =6505.6875m

    =6.51km.

    What exactly am I doing wrong here? ..
     
    Last edited: Jan 15, 2012
  2. jcsd
  3. Jan 15, 2012 #2

    Doc Al

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    Staff: Mentor

    Re: Wavelength/Distance

    This is not correct. What's the definition of speed? (When in doubt, check the units.)

    Also: Don't forget that the sound makes a round trip.
     
  4. Jan 15, 2012 #3

    k0k

    User Avatar

    Re: Wavelength/Distance

    Oh, my bad, a silly error. I got it now. Thanks for the tip on sound making a round trip. : )
     
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