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Homework Help: Work with Velocity Help

  1. Oct 2, 2006 #1
    A skier of mass 71 kg is pulled up a slope by a motor-driven cable.
    (a) How much work is required to pull him a distance of 55 m up a 30° slope at a constant speed of 1.1 m/s

    I'm having trouble trying to figure out where velocity comes into play here. Originally I was using the equation W=Fcosø ∆r and I found F using F=mgsinø. But my homework says this is wrong so I'm begging someone to help me out here.
    Thanks
     
  2. jcsd
  3. Oct 2, 2006 #2

    Hootenanny

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    You can answer this question one of two ways;

    (1)Reslove the forces and find the tension in the cable, then multiply by the distance traveled up the slope.

    (2)Find the work done against gravity (W = mgh).
     
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