Hi all, I just have a troublesome time wrapping my head around the concept of moment of inertia of a cylinder inside a cylinder. For example, in the attached figure(adsbygoogle = window.adsbygoogle || []).push({});

The moment of inertia of the cylinder with radius 'r' around the point o, according to my understanding should be

[itex] I_o = I_s+ m (R-r)^2[/itex]

Where[itex] I_o [/itex] is the moment of inertia around point o

[itex] I_s [/itex] is the moment of inertia of the small cylinder = [itex] 0.5 m r^2 [/itex]

m is the mass of the small cylinder

I believe my understanding above is wrong, since the actual answer is [itex] 1.5 m (R-r)^2 [/itex]. Any help to clarify is appreciated.

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# Moment of Intertia of a cylinder rolling inside a cylinder

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