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Homework Help: Not sure where to start

  1. Oct 20, 2008 #1
    1. The problem statement, all variables and given/known data
    A 8 kg box is initially traveling on a horizontal surface at a speed of 11 m/s and comes to rest after 46 meters due to the force of friction. If the coefficient of static friction is 1.21 times more than the coefficient of the kinetic friction, what is the minimum horizontal force needed in Newtons in order to move the box again?

    2. Relevant equations
    i drew out all my forces but not sure where to go from here

    3. The attempt at a solution
    All i found so fare was the Fn=78.48
    Last edited: Oct 20, 2008
  2. jcsd
  3. Oct 20, 2008 #2


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    Homework Helper

    Welcome to PF.

    You need to first determine the force that the kinetic friction induced to slow it down.

    Knowing that, you can determine the u of kinetic friction and then to figure the u of static friction that you can use to figure the force that needs to be overcome again.
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