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Homework Help: Stupid Piano. Help!

  1. Mar 14, 2005 #1
    A 393 kg piano slides 3.7 m down a(n) 27° incline and is kept from accelerating by a man who is pushing back on it parallel to the incline. The effective coefficient of kinetic friction is 0.40.
    (a) Calculate the force exerted by the man.
    (b) Calculate the work done by the man on the piano.
    (c) Calculate the work done by the friction force.
    (d) Calculate the work done by the force of gravity.
    (e) Calculate the net work done on the piano.
  2. jcsd
  3. Mar 15, 2005 #2


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    What have you done so far on the question? Can you post it please? What are your ideas on how to attack it? We can guide you from there. But not do a whole problem from scratch for you.
  4. Mar 15, 2005 #3
    the whole problem can be solved by using one equation, the work energy theorem:
    [tex] \Delta W = \Delta E_k + \Delta E_g + \Delta E_s + \Delta E_f + F_man [/tex]

    you should know what each segment eans in the equation.
    for ex. [tex] \Delta E_k = \frac{1}{2}m{v_{2}}^2 - \frac{1}{2}m{v_{1}}^2 [/tex]
    [tex] \Delta E_p = mgh_2 - mgh_1 [/tex]

    If you need more help, please indicate which part of the problem you dont understand.


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