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I'm an ocean engineer who's getting old and slow. If I have a half-cylinder mass on a shaft where I'd like to be able to quantify energy (which I think I have right) and then have some way of relating that to potential power output.

What I have so far:

m=18.6 kg

Length=0.305m

radius=0.07m

Mass moment of inertia (I) = 0.5mr^2

Rotational KE (Er) = 0.5Iw^2

w=60rpm=0.159 rad/s

I calculate the Er as 0.00747J

Does this jive? Is there any meaningful way of relating that to power? I do not have a load value (yet), so am just trying to understand what this might be in terms of power if I use some conversion efficiency (thinking alternator load). I am assuming the same motive force that accelerated it to 60 rpm is constant (in some sort of resonance). If I have my calcs/assumptions wrong so far, please correct.

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# Rotating half cylinder energy and power calculation

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