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Homework Help: Quick wave question

  1. Dec 8, 2005 #1

    Nm

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    Can someone tell me how to find the intensity given only the wavelength in meters and amplitude in Pascals? Thanks.
     
  2. jcsd
  3. Dec 9, 2005 #2

    Nm

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    Does anyone know?

    I found the frequency, but I'm a bit confused about why amplitude is in Pascals and how I would find the intensity.
     
  4. Dec 9, 2005 #3
    The intensity in dB is
    [tex]
    I = 20 log_{20} \left[ \frac{P}{P_{0} \right]
    [/tex]
    Where [tex]P[/tex] is the pressure of the wave in pascals and [tex]P_{0} = 2x 10^{-5} \frac{N}{m^2}[/tex].

    Actually I've got a conflicting source that says "Intensity is a measure of the sound energy that passes through a given area each second."
     
    Last edited: Dec 9, 2005
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