Moment of inertia for a thin rod

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SUMMARY

The moment of inertia for a 750 g ball at the end of a thin rod with a radius of 1.2 m is calculated using the formula I = m * r², resulting in an inertia of 0.675 kg·m². To maintain constant angular velocity against an air resistance force of 0.045 N, the required torque can be determined using the formula τ = r * F, yielding a torque of 0.054 N·m. The discussion emphasizes the importance of showing work in homework-related queries to facilitate effective assistance.

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A small 750 g ball on the end of a thin, light rod is rotated in a horizontal circle of radius 1.2 m.
(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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