Hi. I have problem calculating the moment of inertia of a hollow cylinder if an extra mass in shape of smaller solid cylinder is embedded a distance x from the center of the larger cylinder.(adsbygoogle = window.adsbygoogle || []).push({});

Firstly, I use the moment of inertia of a hollow cylinder, which is [tex]I_{larger cylinder}=m_2R_2^2[/tex]. I also know that the moment of inertia for the small solid cylinder is [tex]I=0.5 M_1r_1^2[/tex]. Using the parallel axis theorem, I can calculate the moment of inertia of the whole thing, which is [tex]I_{total}=m_2R_2^2 + 0.5 M_1R_1^2 + M_1x^2 [/tex]. Is that right?

Secondly, how can I calculate the moment of inertia of the whole cylinder about P? Can i use the parallel axis theorem once again to 'move' the axis a distance R? So that the whole inertia will be [tex]I_{total}=m_2R_2^2 + 0.5 M_1R_1^2 + M_1x^2 + (m_2+M_1)R^2[/tex]?

http://www.geocities.com/andre_pradhana/cylinderkendro2.JPG

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# Homework Help: Moment of Inertia

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