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Homework Help: Work and Power problem

  1. Dec 11, 2008 #1
    1. The problem statement, all variables and given/known data

    A tractor pulls a wagon with a constant force of 700N at a constant speed of 20.0 km/h.
    a) How much work is done by the tractor in 3.5min
    b) What is the tractor's power output?
    ANSWERS: a)8.16 x 10^6 J//b) 3888.8 watts
    2. Relevant equation
    P=W/t or P=Fv



    3. The attempt at a solution
    P=Fv
    P=700N x 20.0
    P=14000J

    Pt=W
    14000W x 210seconds=W
    W=2940000J

    I've been trying for over an hour now and I just can't get the answer. Any help will be greatly appreciated.
     
  2. jcsd
  3. Dec 11, 2008 #2

    rl.bhat

    User Avatar
    Homework Helper

    Convert km/h to m/s.
     
  4. Dec 12, 2008 #3
    I realized it about 5 seconds before you posted haha. Thank you very much!
     
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