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Question about coefficient of kinetic friction

  1. Oct 16, 2005 #1
    A hockey player hits a puck with her stick, giving the puck an initial speed of 5.0 m/s. If the puck slows uniformly and comes to rest in a distance of 20 m, what is the coefficient of kinetic friction between the ice and the puck?

    I know that this question must be rather easy, and that my mind has missed some logical leap in order to complete it.

    Given the equation for kinetic friction (I can't format, so I'm not sure how to write this...)

    f(sub k)=(mu)(normal force)

    How can I solve for the coefficient (f sub k) without the mass? It seems that without the mass I am stuck.
  2. jcsd
  3. Oct 16, 2005 #2


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    You have a force (friction) you need to find the acceleration. What happens when you equate your friction force to Newton's Third, F=ma?
  4. Oct 16, 2005 #3
    Wonderful things happen.

    I wonder why I didn't think of that. -blush-

    Thank you!
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