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Question
I am currently a junior in high school taking honors physics and am having some serious trouble solving the below problem. Thanks in advance!

A 2.44 kg block is pushed 1.55 m up a vertical wall with constant speed by a constant force of magnitude F applied at an angle of 69.6 degrees with the horizontal. The acceleration of gravity is 9.8 m/s2 .
If the coefficient of kinetic friction between the block and wall is 0.691, find the work done by F .
Answer in units of Joules

Answer
Resolve the force, F, into two components, Fv (vertical) = Fsin(69.6) and Fh (horizontal) =
Fcos(69.6).  The frictional force = 0.681Fh.  The vertical force has to overcome mg which equals 2.44(9.8) and the frictional force.  So Fsin(69.6) = 23.91+0.681Fcos(69.6).  
Solve for F and then the work = F(1.55)  

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Richard J. Raridon

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I can answer most questions in undergraduate physics courses, including electricity and magnetism, atomic and nuclear, mechanics and optics.

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