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Physics 11 work done by friction

  1. Dec 20, 2006 #1
    1. The problem statement, all variables and given/known data

    Magen's mass is 28kg. she climbs the 4.8m ladder of a slide and reaches a v3elocity of 3.2m/s at the bottom of the slide. How much work was done by friction on Magen

    2. Relevant equations


    3. The attempt at a solution
    I really just have no idea, could someone just guide me in the right direction or give me the first step?
  2. jcsd
  3. Dec 20, 2006 #2
    Think about the following things:
    1. How much mechanical energy does she have at the top of the slide?
    2. At the bottom of the slide?
    3. What could have happened on the slide that would have changed the mechanical energy?
  4. Dec 20, 2006 #3

    Doc Al

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    Staff: Mentor

    Just keep track of the mechanical energy. If any is missing, assume it was lost to friction. What's her energy at the top? At the bottom? Subtract!

    (Saketh beat me too it! :smile: )
  5. Dec 20, 2006 #4
    so would i use Eki+Epi=Ekf+Epf?
  6. Dec 20, 2006 #5
    oooh ok i think i get it...i think. The answer i came up with was 1.2x10^3
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