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Compute the mechanical power provided by...

Compute the mechanical power provided by the internal forces within the body of a person of mass 80 kg who runs up a flight of stairs rising a vertical distance of 3m in 3s.

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If the body's KE is approximately constant during climb, the only change in energy is the gravitational potential energy which is mgh `=(80 xx 9.8 xx3) J = 2352 J.` Thus, power, `(2352J)/(3s) = 784W`
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