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Suppose I am trying to find the work done in bringing a resting cylinder to an angular speed of 8 rad/s.

Why is it INCORRECT to find the corresponding tangential velocity at a point on the outer surface of the cylinder (using angular speed * radius = tangential speed) and use the translational (0.5mv^2) work-kinetic energy theorem?

Why MUST we use the rotational version with I and angular speed?

Thank you.

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# Translational vs. Rotational Kinetic Energy

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