Calculating Forces and Work on a Sliding Piano

AI Thread Summary
A 393 kg piano slides down a 27° incline, and a man pushes back against it to prevent acceleration, with a coefficient of kinetic friction of 0.40. To solve the problem, the work-energy theorem can be applied, which relates the work done by various forces to changes in kinetic and potential energy. Key calculations include determining the force exerted by the man, the work done by him, the friction force, gravity, and the net work on the piano. Participants are encouraged to share their progress and specific areas of confusion for targeted assistance. Understanding each component of the work-energy equation is essential for solving the problem effectively.
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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.
 
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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.
 
the whole problem can be solved by using one equation, the work energy theorem:
\Delta W = \Delta E_k + \Delta E_g + \Delta E_s + \Delta E_f + F_man

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

If you need more help, please indicate which part of the problem you don't understand.

Regards,

Nenad
 
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