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Homework Help: Integrals, Physics

  1. Sep 19, 2005 #1

    tmc

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    I have this formula, and I just cant seem to be able to find any sensible answer:

    [tex]V^2_\textrm{rms}=\frac{1}{T}\int_{0}^{T}V^2_0sin^2(2ft\pi)dt [/tex]

    Depending on what I do, I either get an obviously wrong answer, 0, or [tex]V_0[/tex].
     
    Last edited: Sep 19, 2005
  2. jcsd
  3. Sep 19, 2005 #2

    George Jones

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    The stuff under the integral sign needs to be squared. This is the S part of rms.

    Regards,
    George
     
  4. Sep 19, 2005 #3

    tmc

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    yeah, my bad. Edited it.
    Still dont get how to solve it though.
     
  5. Sep 19, 2005 #4

    George Jones

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    Use [itex]cos(2\theta) = 1 - 2sin^2 (\theta)[/itex] and [itex] f = 1/T[/itex].

    Regards,
    George
     
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