A 300 g ball and a 500 g ball are connected by a 60-cm-long massless rigid rod. The structure rotates about the center of the rod with angular velocity 5 rad/s. What is the rotational kinetic energy?(adsbygoogle = window.adsbygoogle || []).push({});

Attempt:

the rotational kinetic energy is given by

KEr = (1 / 2) I ω^2

where I is the moment of inertia if the ball is considered as a solid sphere then we get that

I = (2 / 5) M R^2 for a solid sphere

but i have a question what should i use for M and R?

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# Homework Help: Rotational Kinetic Energy

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