A uniform, solid sphere of mass 3.2 kg and diameter 63 cm is rotating about its diameter at 230 rev/min. What is the kinetic energy of rotation?(adsbygoogle = window.adsbygoogle || []).push({});

230rev/min= 24.1 rad/s

I know that KE=1/2Iw^2 and interia of a solid sphere is I=2/5MR^2

I=(2/5)(3.2)(.63)^2

=.508032

KE=(1/2)(.508032)(24.1)^2

=147.5 J

For some reason my answer is wrong. Am I missing something? What am I doing wrong?

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# Homework Help: Rotating Ball

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