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Homework Help: Mechanics Problem

  1. Jun 14, 2007 #1
    1. The problem statement, all variables and given/known data

    In a simple pendulum the string supporting the bob is replaced by a uniform rod of length L and mass M.Find the nw time period for small oscillations.Mass of the bob m.

    Any help how to do it correctly???

    2. Relevant equations
    3. The attempt at a solution

    Any help how to do it correctly???
     
  2. jcsd
  3. Jun 14, 2007 #2
    i guess the mass of string was neglected
    and now since the rod has mass M, the CG of the system has changed
     
  4. Jun 14, 2007 #3

    cepheid

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    Basically, this is a physical pendulum now. Sure, the centre of mass has changed. So has the moment of inertia. If I remember right, the moment of inertia of a physical pendulum determines its period, but you'll have to derive the exact relation.
     
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