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Homework Help: Lagrangian mechanics

  1. Mar 8, 2005 #1
    I want to calculate the movement of the rod in the picture, but I don't know how to put up the Lagrangian for the problem.
    I have the Shear modulus, [tex]\mu[/tex], for the material and M>>m and [tex]\theta = 0[/tex]. I need the Lagrangian and from there on I think I can manage with the calculations myself.


    Attached Files:

    • rod.jpg
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  2. jcsd
  3. Mar 8, 2005 #2
    Can you post the wording of the problem.
  4. Mar 9, 2005 #3
    Well, I have come up with the problem myself.
    What I am trying to get is an equation for the motion of the rod, or cantilever if you will. My problem is that I am not sure how to relate the force influencing the heavy block the rod is attached to, to the rod.
    I think I need to make a connection between the Shear modulus, or the elasticity modulus of the material the rod and the block is made of to the force which is transferred to the rod.

    I will settle for some help using usal mechanics on how the force is transferred from the block to the rod.

  5. Mar 11, 2005 #4
    Ok, let me refrase my question a bit.
    Can somebody tell me how the rod goes about to "sway" when a impulse is applied on the bigger block with mass M?
    If you know a book or a homepage, which you could refer me to for this problem, I would apperciate that as well.
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