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Homework Help: Elastic collision

  1. Sep 8, 2010 #1
    1. The problem statement, all variables and given/known data

    A body of mass, m makes a head on perfectly elastic collision with a body of mass, M initially at rest. Show that

    [tex]\frac{\triangle E}{E_o}=\frac{4(\frac{M}{m})}{(1+\frac{M}{m})^2}[/tex]

    2. Relevant equations

    3. The attempt at a solution

    Momentum: [tex]mu_1=mv_1+Mv_2[/tex]

    [tex]\triangle E= \frac{1}{2}mv_1^2+\frac{1}{2}Mv_2^2-\frac{1}{2}mu_1^2[/tex]
  2. jcsd
  3. Sep 8, 2010 #2


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    Staff: Mentor

    If collision is ellastic, delta E as defined (final minus initial, right?) should equal zero.

    Or am I missing something?
  4. Sep 8, 2010 #3
    Thanks Borek! Exactly, i think it's meant to be inellastic collision. I'll give it a try.
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