A small 750 g ball on the end of a thin, light rod is rotated in a horizontal circle of radius 1.2 m.(adsbygoogle = window.adsbygoogle || []).push({});

(a) Calculate the moment of inertia of the ball about the center of the circle.

(b) Calculate the torque needed to keep the ball rotating at constant angular velocity if air resistance exerts a force of 0.045 N on the ball. Ignore the rod's moment of inertia and air resistance.

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# Homework Help: Moment of inertia for a thin rod

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