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Homework Help: Elliptic pendulum

  1. Mar 11, 2012 #1
    1. The problem statement, all variables and given/known data

    A uniform rod AB of mass M and length 2l attatched to a slider at A which is constrained to move along a smooth horizontal wire. The rod, which is subject to gravity, is free to swing in the vertical plane containing the wire. Using Ω (the angle between rod and vertical) and x coordinate of the centre of mass, find an expression for the kinetic and potential energies, deduce Lagrange's equations. Show that the Lagrangian is regular.

    2. Relevant equations

    3. The attempt at a solution
    I know I have to treat the rod as a continuum, but I can't get around it....

    Sorry it doesn't seem like I've done much but I've tried every way I know and nothing's working, any advice would be greatly appreciated. Thank you

    Could you please start me of....I know v=-2lmcosθ

    But to get T could you please help me.... I don't know what my x coordinate is
  2. jcsd
  3. Mar 12, 2012 #2
    KE = 1/2[Mx.^2 + θ.^2 Ml^2 sin^2(θ)]

    I have seemed to get this...could any1 please check if I have done this right
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