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Homework Help: Work done by friction?

  1. Sep 19, 2010 #1
    1. The problem statement, all variables and given/known data

    You are pushing a refrigerator across the floor of your kitchen. You exert a horizontal force of 297 N for 6.7 s, during which time the refrigerator moves a distance of 2.8 m at a constant velocity.

    What is the work done by friction?

    2. Relevant equations

    W=fv
    w=f(d/t)

    3. The attempt at a solution

    w=297(2.8/6.7) = 124 J.

    Why is this answer incorrect?
    Any info to the right direction is much help :) thanks
     
  2. jcsd
  3. Sep 19, 2010 #2
  4. Sep 19, 2010 #3
    Edit - Right, it'll be -FΔx.

    Thanks.
     
    Last edited: Sep 19, 2010
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