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

You are to design a rotating cylindrical axle to lift 800N buckets of cement from the ground to a rooftop 78.0m above the ground. The buckets will be attached to a hook on the free end of a cable that wraps around the rim of the axle; as the axle turns, the buckets will rise.

What should the diameter of the axle be in order to raise the buckets at a steady 2.00 cm cm/s when it is turning at 7.5rpm?

If instead the axle must give the buckets an upward acceleration of 0.400 m/s^2, what should the angular acceleration of the axle be?

2. Relevant equations

KE=0.5 I w^2

GPE = mgh or force x height

I=0.5 m r^2 (for a disc/cylinder)

3. The attempt at a solution

GPE=800x78=62400

Then i would have though KE=GPE but as theres no mass for the cylinder that can't be right

thanks in advance

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# Homework Help: Rotation - lifting buckets

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