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Homework Help: Kinetic Friction of jet powered skiis

  1. Oct 3, 2007 #1
    1. The problem statement, all variables and given/known data
    Joe, whose mass is 80kg, takes off across level snow in his jet powered skiis. The skiis have a thrust of 186N and a coefficient of kinetic friction on snow of 0.1. Unfortunately, the skiis run out of fuel after only 8 s. What is Joe's top speed? How far has Joe traveled when he finally coasts to a stop?

    2. Relevant equations

    3. The attempt at a solution
  2. jcsd
  3. Oct 3, 2007 #2


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    Please show some work.

    Joe's mass (80 kg) is subjected to a force 186 N, but experiences a retarding (friction) force. The coefficient of friction is 0.1.

    So determine the acceleration, from which speed can be determined at the end of 8 s.

    Then with that speed, Joe decelerates with friction, so determine how far based on the maximum speed (magnitude of velocity) through the distance where he stops.

    Refer to this - http://hyperphysics.phy-astr.gsu.edu/hbase/mot.html
  4. Oct 3, 2007 #3
    I got his top speed to be 10.76 m/s by using the frictional force in the equation. I just don't know which equation to use from there.
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