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Homework Help: Understanding question

  1. Oct 6, 2005 #1
    Ok, i just need to verify what this question means:

    A baseball pitcher throws a ball straight up into the air at a speed of 20 m/s as a protest against the umpire's calls. In the process, he moves his hand through a distance of 1.5 m. If the ball has a mass of 0.15 kg, find the force he exerts on the ball to give it this upward speed. Note that the force of gravity is acting against the motion of the ball.

    Ok, so i just have a question on what the significance of the "1.5 m " distance.
  2. jcsd
  3. Oct 6, 2005 #2


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    HINT: Work = Force X distance
  4. Aug 26, 2009 #3
    I see what is going on... W= Ek so, F*s = ((m*v*v)/2) . The speed is related to the Force and the distance the force was applied over.

    I new that F= m*a. so speed is related to force over time. I never really considered the distance that a force is applied over.

    If Hitokiri is still visiting this forum It would be interesting to know if Tides hint was of help.
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