(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A 54.2 kg student climbs a 6.95 m rope and stops at the top. What must her average speede in order to match the power output of a 110 W lightbulb?

2. Relevant equations

PE=mgh

KE=1/2mv^2

W=(Xf-Xi)(cos theta)(F)

W= delta KE

PE+KE = PE+KE (before and after)

3. The attempt at a solution

I know that the PE for the student is 3691.6 J at the top of the rope. And KE is zero at the top of the rope, so PE at the bottom of the rope would be 0, and KE would be 3691.6.

I don't know what to do next and I don't know how to use the 110 W light bulb.

Please help. Thank you.

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# Conservation of energy

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