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Question about the average force?

  1. Jun 7, 2010 #1
    Okay we all know that the average force equation is

    ΔP = FΔT
    F = ΔP / ΔT

    Say I throw a ball at the wall and it has and the collision is elastic. Therefore, the initial momentum equals the final momentum and therefore.

    ΔP = 0

    I still know that there is a force exerted on the wall, but how do I find it if ΔP = 0?
  2. jcsd
  3. Jun 7, 2010 #2
    Don't forget that momentum is a vector quantity. So if it hits the wall with momentum magnitude P, the change in momentum is 2*P , to account for the reverse in direction.

    Hope this helps,

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