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Ball thrown upward and another is dropped

  1. Sep 17, 2007 #1
    A ball is thrown upward from the ground with a initial speed of 25 m/s; at the same instant, another ball is dropped from a building 15 m high. After how long will the balls be at the same height?

    I'm not even sure how to start it so help!
  2. jcsd
  3. Sep 17, 2007 #2
    Draw a picture, with the applied forces.
  4. Sep 17, 2007 #3


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    First, consider just one ball.
    Can you determine its motion as a function of time?
  5. Sep 17, 2007 #4
    I'm not sure what formula to use to determine the time and I drew a pic but it didn't really help.
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