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Homework Help: What is the original kinetic energy of the player?

  1. Oct 28, 2006 #1
    A 95-kg football player traveling 5.0 m/s is stopped in 1.0 s by a tackler.
    a. What is the original kinetic energy of the player?
    b. What average power is required to stop him?

    a.
    K=(1/2)mv2
    K=(1/2)(9500 g)(5.0 m/s)2= 118,750 J
    b.
    P=w/t
    P=118750 J/1.0 s= 118750 W


    Would this be correct because of the work-energy principle?
     
  2. jcsd
  3. Oct 28, 2006 #2

    radou

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    Homework Helper

    Looks okay, but I don't see why you should convert [kg] to [g].
     
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