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Homework Help: Work and Power of Skier

  1. Oct 7, 2008 #1
    1. The problem statement, all variables and given/known data
    A skier of mass 70.0 kg is pulled up a slope by a motor-driven cable.
    How much work is required to pull the skiera distance of 60.0m up a 30 degree slope (assumed frictionless) at a constant speed of 2.00 m/s?


    2. Relevant equations
    W=F (delta)r cos(theta)


    3. The attempt at a solution
    (delta)r= 60.0m
    (theta)=30.0 degrees
    Force=60sin30=30 J


    Is this the correct start?
    1. The problem statement, all variables and given/known data



    2. Relevant equations



    3. The attempt at a solution
     
  2. jcsd
  3. Oct 9, 2008 #2

    Hootenanny

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    Staff Emeritus
    Science Advisor
    Gold Member

    It's all good up until this point:
    Firstly force is measured in Newton's and not Joule's. Secondly, how did you calculate the force acting on the skier?

    HINT: This problem is much more straight forward if one simply considered the gravitational potential energy of the skier.
     
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