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Homework Help: Physics help please

  1. Sep 26, 2004 #1
    hi, if anyone knows how to do this question, could you please get me started?????

    A ball is thrown upward from the ground with an initial speed of 23.2 m/s; at the same instant, a ball is dropped from a building 16.1 m high. After how long will the balls be at the same height?
  2. jcsd
  3. Sep 26, 2004 #2
    Find a formula for the height of the first ball as a function of time. call this h_1(t).

    Find a formula for the height of the second ball; call that h_2(t).

    Then what can you do with the two height formulas to find out when the two balls are at the same height?
  4. Sep 26, 2004 #3
    thanks, i figured it out! :)
  5. Sep 26, 2004 #4
    you're welcome. :smile:
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