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Homework Help: Power Output Question?

  1. Nov 15, 2008 #1
    1. The problem statement, all variables and given/known data
    A weightlifter is able to lift 250 kg 2.00m, in 2.00s. What is his power output?


    2. Relevant equations
    W=M x N
    P = W/Change t


    3. The attempt at a solution
    250 x 2 = 500 (I thought that this was work) so then I divided by time (2.00s) to get power. The answer is not right. It should be 2.45 kW. Please tell me what I am doing wrong.
     
  2. jcsd
  3. Nov 15, 2008 #2
    Work = m*g*h, you missed a "g" in there, so you are off by a factor of 9.81
     
  4. Nov 16, 2008 #3
    I got it. thank you!
     
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