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Homework Help: Baseball acceleration physics

  1. Oct 2, 2006 #1
    An autographed baseball rolls off a 1.2m high desk & strikes the floor 0.37m away from the desk. The acceleration of gravity is 9.81m/s^2. How fast was it rolling on the desk before it fell off?
     
  2. jcsd
  3. Oct 2, 2006 #2

    kreil

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    Gold Member

    Analyze the problem vertically using the equation

    [itex]d=v_it+\frac{1}{2}at^2[/itex]

    since vi is zero, solving for time yields:

    [itex]d=\frac{1}{2}at^2 \implies t=\sqrt{\frac{2d}{a}}[/itex]

    Now, use this time to analyze the problem horizontally. It moved a total distance d in time t, so use the equation

    [itex]v_i=\frac{d}{t}[/itex]

    and this will yield the balls initial horizontal velocity.
     
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