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Final Velocity after Collision

  1. Apr 21, 2010 #1
    1. The problem statement, all variables and given/known data
    Two balls roll towards each other. Ball A moves to the right with velocity 5 m/s and ball B moves to the left with velocity 3m/s. If both balls have the same mass, m=50kg, determine the final velocity of them if they move off together after collision. In which direction will they move?

    2. Relevant equations

    F = M(Vf - Vi)/2 (is this correct?)
    Vf = Vi + Acceleration * Time (is this correct?)
    V = d/t

    3. The attempt at a solution
    M = 50kg
    Vi of ball A = 5m/s
    Vi of ball B = 3m/s
    A = ?
    T = ?

    Ball A:
    Vf = 5 + A * T

    Using formula V = d/t
    5 = d/t I stuck, don't know how to work this out. Any hints?
  2. jcsd
  3. Apr 21, 2010 #2

    Filip Larsen

    User Avatar
    Gold Member

    You need to employ conservation of momentum.
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