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Homework Help: Conservation of Energy?

  1. Oct 31, 2007 #1
    1. The problem statement, all variables and given/known data
    Two heavy balls of equal mass M are attached to the long but light metallic rod standing
    on the floor. The rod with the balls falls to the floor. Find the velocity of each ball at the moment
    when the rod hits the ground. Neglect mass of the rod and the friction between the balls and the

    2. Relevant equations

    3. The attempt at a solution
  2. jcsd
  3. Oct 31, 2007 #2
    Conservation of linear momentum may help. Friction is negligible, conservation of energy may also be of help.

    A question: Can you explain why reaction force (by the ground) on the ball, touching ground at all moments, does no work on the two-ball system!
    Last edited: Oct 31, 2007
  4. Oct 31, 2007 #3


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    Equations for Velocity:

    1)F=Ma ->
    f(a) => V=u+at

    V=u+ Ft/m
    Last edited: Oct 31, 2007
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