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Homework Help: Static and kinetic friction

  1. Oct 20, 2011 #1
    1. The problem statement, all variables and given/known data

    When you push a 1.55 kg book resting on a tabletop it takes 2.50 N to start the book sliding. Once it is sliding, however, it takes only 1.50 N to keep the book moving with constant speed. What are the coefficients of static and kinetic friction between the book and the tabletop?

    2. Relevant equations

    Force of static/kinetic friction= "mu" (looks like a u with a tail in the front) * normal force

    3. The attempt at a solution
  2. jcsd
  3. Oct 20, 2011 #2


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    Homework Helper

    Welcome to PF!
    Look at the bottom of my post; you'll see "μ" and some other symbols you can copy and paste into a post. There are more of them here:
    https://www.physicsforums.com/blog.php?b=346 [Broken]

    I can't help you much until you attempt the problem. Can you at least write out the formula for friction force? It will have the μ in it, so solve for that. See if you can calculate the other unknowns in the formula. Let us know what trouble you have and we'll be glad to help.
    Last edited by a moderator: May 5, 2017
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