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Homework Help: Elastic collision algebra

  1. May 3, 2005 #1

    tony873004

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    In an elastic collision problem, I'm supposed to solve for the mass of the 1st car (m1). I get stuck here. How do I re-write this to solve for m1?

    [tex]u_2=\frac{2*m_1v_1}{m_1+m_2}[/tex]
     
  2. jcsd
  3. May 3, 2005 #2
    Thats the equation for an inelastic collision, but

    [tex] u_2m_1+u_2m_2-2m_1v_1 = 0 [/tex]

    [tex] u_2m_1 - 2m_1v_1 = -u_2m_2 [/tex]

    [tex] m_1(u_2 - 2v_1)= -u_2m_2 [/tex]

    [tex] m_1 = \frac{-u_2m_2}{u_2-2v_1} [/tex]
     
  4. May 3, 2005 #3

    tony873004

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    Thanks, whozum. That worked !
     
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