A man stands on a massless platform that is free to rotate in the horizontal pla

Question

A man stands on a massless platform that is free to rotate in the horizontal plane. He holds a weight in each hand that has mass m. He has his arms extended so that they have length S. The system is set into rotation so that the angular velocity of the platform is w0.

Assume the mans mass can be neglected compared to the weights. What force would have to be applied to one of the weights at the distance S so that in t0 seconds the platform, which is initially at rest, is rotating with angular velocity w0?

Explanation / Answer

Using newton's second law of rotation (at the moment of answering the equation display was having trouble i hope the equations are well understood)

Torque=Inertia * angular acceleration

since it starts from rest

Torque=Inertia * wo/to

F * S = (mS^2+mS^2) * wo/to

F=2*m*S*wo/to

For torque calculations calculation i assumed a distance S from the center or rotation and a + sense torque

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