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

Q: A flywheel of moment of inertia 0.32kg/m^2 is rotated steadily at 120rad/s by a 50W electric motor. Find the kinetic energy of the flywheel.

2. Relevant equations

What is the best way to work this out? Am I using the right equations?

Can I simply substitute the angular rotation (120rad/s) instead of the velocity v in KE=(1/2)mv^2

3. The attempt at a solution

This is what I tried doing:

KE = (0.5).(m).(120)^2 but I still don't know the mass

Tried to use ω = v/r but I was not given the radius

To use power, I tried P = F.v -> P = m.a.v but I get stuck again because of mass and acceleration.

Where: ω = angular speed; v = linear velocity; m = mass; P = Power; F = force; KE = Kinetic Energy; a = acceleration

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# Finding the KE of a flywheel

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