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Homework Help: Tennis Ball Collide With Train Prob.

  1. Aug 2, 2006 #1
    hi all,

    the qns is when a tennis ball collide with a train, can the ball stop the train for a split sec, since during collision, the ball have to change direction so velocity at some point in time is equal to zero. Being at V= 0 for that split sec, and since the ball is in contact with the train, we can deduce that the train also stop temporaryly.

    I know the qns has been ask B4. At that time, the answer given was that acceleration for the change of velocity is infinity, so V can nv be zero.

    Now the REAL qns is how do u prove it mathematically(not logically)
    that acceleration is infinity?

    P.S. i tried to search for the thread but couldn't find it.(honest)
  2. jcsd
  3. Aug 2, 2006 #2


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    The other thread was locked...

    A quick search for train gives: https://www.physicsforums.com/showthread.php?t=125266&highlight=train

    Definitive post:
    Last edited: Aug 3, 2006
  4. Aug 2, 2006 #3
    haha thx for helping me find the tread i understand it now
  5. Aug 2, 2006 #4


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    Gold Member

    Hey! I've been quoted!
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