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

2 problems.

1: A man lifts a 91kg person straight up a distance of 1.2m in 0.51s. What power is used to do this?

2: 3.00x10^2kg piano is lifted at a steady velocity from ground to a height of 10.0m. The crane doing the lifting has a steady power of 4.00x10^2W. What time does it take to do this?

2. Relevant equations

Both equations should be able to use P=Fd/t

3. The attempt at a solution

With both problems, the book states constant velocity so the F=ma=0, which doesnt make sense because that would make the answer 0.

Is there another way of finding force that i am forgetting?

Thanks

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# Homework Help: Crane power homework question

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