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Homework Help: Sound Level (trouble setting up equation)

  1. Oct 17, 2007 #1
    Sound Level and Intensity (trouble setting up equation)

    A certain sound source is increased by 30 dB. By what multiple is its intensity increased?

    This is what I have set up so far, but I do not think it is correct..

    [tex]\beta_1=10\log\frac{I_1}{I_0}[/tex] and [tex]\beta_2=40\log\frac{I_1}{I_0}[/tex]
    So,
    [tex]\frac{\beta_1}{\beta_2}=\frac{10\log\frac{I_1}{I_0}}{40\log\frac{I_1}{I_0}}[/tex]

    and from there I am jammed...we have been using product and sum logs so far...but this expression does not fit the bill..so I believe I have made a conceptual error in setting up the equation.

    Do you see my error?
    Casey
     
    Last edited: Oct 17, 2007
  2. jcsd
  3. Oct 17, 2007 #2
    This is killing me.

    Edit: I think I found the correct relationship....how about beta2=beta1+30

    so beta2-beta1=30....and then I should be able to use properties of Logs.....


    ...that worked.

    Sweeeeeeeet.
    Casey
     
    Last edited: Oct 17, 2007
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