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Determining velocity of objects after collision

  1. Apr 17, 2012 #1
    "A projectile of mass m1 moving with speed v1 in the -x direction strikes a stationary target of mass m2 head-on. The collision is elastic. Use the Momentum Principle and the Energy Principle to determine the final velocities of the projectile and target, making no approximations concerning the masses. "

    All I've gotten so far is that:

    P1f + P2f = P1i + P2i

    but v2i = 0 SO P2i = 0

    am I on the right track? I'm pretty much lost at this point.
  2. jcsd
  3. Apr 17, 2012 #2


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    Homework Helper

    Yes, P2i = 0, go ahead. You have also conservation of energy.

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