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Homework Help: Length of wire

  1. May 23, 2008 #1
    [SOLVED] length of wire

    1. The problem statement, all variables and given/known data

    A wire of mass 1.1 g is under a tension of 100 N. If its third overtone is at a frequency of 750 Hz, calculate the length of the wire.

    3. The attempt at a solution

    v = sqrt(FL/m) = 301.5*sqrt(L)

    fn = n*v/(2*L) --> L = n*v/(2*fn) --> L = 0.36 m

    The book says 0.65 m. Am I wrong?
  2. jcsd
  3. May 23, 2008 #2

    Chi Meson

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    The third "overtone" is the fourth "harmonic."

    Other than that, you did everything right. (well, your final formula is incorrectly written, but you solved correctly for n=3.)
    Last edited: May 23, 2008
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