A skier of mass 55.0 kg slides down a slope 11.7 m long, inclined at an angle theta to the horizontal. The magnitude of the kinetic friction is 41.5 N. The skier's initial speed is 65.7 cm/s and the speed at the obttom of the slope is 7.19 m/s. Determine the angle theta from the law of conservation of energy. Air reistance is negligible.(adsbygoogle = window.adsbygoogle || []).push({});

The answer is 17.5 degrees, but the work is hard for me to start at.

From what I've learned, we use Et1 = Et2, and I can find theta from 11.7 sin theta which is delta y. I get 12.9 degrees from this. I know this is incorrect, and the friction force needs to be added in somewhere, I just don't know where.

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# Law of Conservation of Energy of a skier

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