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Homework Help: Finding stopping distance given coefficient of kinetic friction and mass

  1. Feb 20, 2009 #1
    1. The problem statement, all variables and given/known data
    Bobsled

    A bobsled run leads down a hill as sketched in the figure above. Between points A and D, friction is negligible. Between points D and E at the end of the run, the coefficient of kinetic friction is µk = 0.4. The mass of the bobsled with drivers is 210 kg and it starts from rest at point A.

    Find the distance x beyond point D at which the bobsled will come to a halt.


    2. Relevant equations
    PE=mgy
    (delta)x = ½ v_o2/ mg


    3. The attempt at a solution
    I thought the bottom equation should be the right approach but I dont know how to find the velocity given the coefficient of kinetic friction and mass of the sled
    1. The problem statement, all variables and given/known data



    2. Relevant equations



    3. The attempt at a solution
     

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  3. Feb 20, 2009 #2

    tiny-tim

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    Science Advisor
    Homework Helper

    Hi disque! :smile:

    (I can't see the picture yet)

    This is an energy question …

    calculate the the work done by friction,

    and use the work-energy theorem, which says that loss of energy equals work done. :wink:
     
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