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Homework Help: Difficult Energy Question. Please Help

  1. Nov 16, 2004 #1
    Prooving crazy formula

    If anyone could help me with this that would be great. I keep getting stuck. Thanks.

    A block slides down a curved frictionless track and then up an inclined plane. the coefficient of kinetic friction between the block and the incline is Uk. Use energy methods to show that the maximum height reached by the block is:


    1 + Uk cot(theta)
    Last edited: Nov 16, 2004
  2. jcsd
  3. Nov 16, 2004 #2


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    The initial kinetic energy is equal to final potential energy minus the work done by the frictional force. Where exactly are you "getting stuck?"
  4. Nov 17, 2004 #3
    Since the track is frictionless, it's path independent, so potential energy just before the block starts to slide is mgh (from gravity). Also you know that the change in thermal energy of the block due to friction is Uk * distance block travels up ramp. Hopefully that will help you some.
  5. Nov 17, 2004 #4


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    It might help us to know what "theta" means.
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