A 14.0 kg block is dragged over a rough, horizontal surface by a 87.0 N force acting at 20.0° above the horizontal. The block is displaced 6.50 m, and the coefficient of kinetic friction is 0.300.(adsbygoogle = window.adsbygoogle || []).push({});

(b) Find the work done on the block by the normal force.

J

(c) Find the work done on the block by the gravitational force.

J

I thought normal force was mg which turned out wrong.

For gravitational force, I tried force times delta r times cos theta, but that also turned out wrong as well.

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# Homework Help: Simple problem, but having a bit of trouble

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