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Stucked in a Qn on wave.

  1. Sep 4, 2005 #1


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    A rope of total mass M and length L is suspended vertically.Show that a transverse wave pulse travel in the length of the rope in a time t=2(L/g)^0.5

    If i take the distance of any point on the rope ,A, from the lower end to be X.
    linear density is M/L
    Tension due to the segment of rope below A is MgX/L
    velocity =(T/linear mass density)^0.5
    if X=L
    V= (L/g)^0.5

    which is not what is needed to be shown. So where am i wrong?
  2. jcsd
  3. Sep 4, 2005 #2


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    Check your calculations !!! and write [tex] v = dx / dt [/tex]
  4. Sep 4, 2005 #3


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    The speed of the wave is not constant. It diminishes as the wave gets closer to the lower end. So to find the time, you have to integrate dx/v.

    (And yes, check your calculations :tongue2:)
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