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Homework Help: Sound Intensity

  1. Sep 26, 2004 #1
    I'm given two things:

    frequency, f = 313 Hz
    intensity, I = 1.13 uW/m^2 (microWatts per square meter)

    I'm supposed to find the amplitude of the air vibrations caused by this sound.

    As always, a push in the right direction is greatly appreciated.
  2. jcsd
  3. Sep 26, 2004 #2
    You need a formula; do you have any? Unfortunately the formulas for this stuff are big and complex.
  4. Sep 26, 2004 #3
    1......v( delta Pm )^2
    - * ------------------- = I

    I think what I'm seeking is sm, in which case

    sm = (delta Pm) / (kB) [k is from (kx - wt)]

    Anyone know a program or website that lets me type scientific equations? This spacing stuff gets old fast.

    If I work those formulas around, I think I get:

    I / k = (1/2)(v)(delta Pm)*sm

    The problem there is I don't know what (delta Pm) would be.
    Last edited: Sep 26, 2004
  5. Sep 26, 2004 #4
    I'm not really sure that whole equation is necessary, but I'm also not sure how to shorten it and figure it out with the two variables given.
  6. Sep 26, 2004 #5
    We do math typesetting on here using a code called Latex. See the sticky about it in General Physics. Sorry, I'm not very familiar with these formulas. Someone will chime in and help! ;)
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