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Homework Help: Totally inelastic collision

  1. Nov 9, 2008 #1
    1. The problem statement, all variables and given/known data
    A bigger, moving, vI]i[/I], collides with a smalled train that is not moving. Assume that after the collision the trains stick together. Assume the trains have different masses (mbig and msmall). Write doen the momentum conservation equation for the scenario. Solve for the final velocity of the two trains, vf

    2. Relevant equations
    conservation of momentum
    m1v1f + m2v2f = m1v1i + m2v2i

    3. The attempt at a solution
    So i decided that m1 = mbig and m2=msmall
    mbigvbig f + msmallvsmall f = mbigvbig i + msmallvsmall i

    since vsmalli is at rest then = 0

    mbigvbig f + msmallvsmall f = mbigvbig i

    (mbig+msmall)*vbigsmall f = mbigvbig i

    vbigsmall f= mbigvbig i/(mbig+msmall)

    is this right??
  2. jcsd
  3. Nov 9, 2008 #2
  4. Nov 9, 2008 #3
    Looks fine by me.
  5. Nov 9, 2008 #4
    ok thanks
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