A 121-kg crate is being pulled across a horizontal floor by a force P that makes an angle of 36.8° above the horizontal. The coefficient of kinetic friction is 0.212. What should be the magnitude of P, so that the net work done by it and the kinetic frictional force is zero?(adsbygoogle = window.adsbygoogle || []).push({});

the work of gravity and the normal force are going to be 0 because they are 90 degrees from the distance that the box is travelling. should the work of kinetic friction be 0 because it says "kinetic frictional force is zero"? that would mean that the net work is equal to the force of P * distance * cos 39.9 and we are looking for the force of P, but we don't know the distance... i'm confused can someone help? thanks

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# Work problem

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