Question is.. how much power does a 45 kg person develop climbing up a vertical ladder 7.0 m high if the average acceleration is 0.25 m/s^2?(adsbygoogle = window.adsbygoogle || []).push({});

This is where I'm at... (so far anyways)

calculate t from d = vt + 1/2at^2 and get value of 7.5 s to climb ladder... but now, how do I calculate Work in order to sub into P=W/t equation...

I have tried this... W = (Fg + Fa)*d = [(45)(9.81) + (45)(0.25)]*7 = 3168.9

and then P= W/t = 3168.9/7.5 = 423 W

Answer in book is 423 W but I am confused as to why I am right.. don't Fg and Fa act in opposite directions on the FBD??

Any help is appreciated

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# Homework Help: Energy and Power Question

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