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Initial speed problem?

  1. Dec 16, 2013 #1
    A ball thrown vertically from ground level is caught 3.0 s later by a person on a balcony who is 14 m above the ground, determine the initial speed of the ball.

    When I first tried doing this problem, I tried using the speed equation of distance/change in time, so I divided 14 by 3 which gave me 4.7 m/s, but according to my study guide the answer is 19 m/s and I'm having a hard time understanding why that's the answer and what equation I would use to solve it. Any help is appreciated, thanks!
  2. jcsd
  3. Dec 16, 2013 #2


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    Hi athena, welcome to PF!

    If you are using displacement = average velocity * time, your result is the average velocity, not the initial velocity. Can you find another equation to use from the list of the kinematic motion equations?
  4. Dec 16, 2013 #3


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    What happens to the speed of the ball after it leaves the thrower's hand?
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