Moment of Inertia of Disk at any point

AI Thread Summary
The moment of inertia of a disc at its center of mass is given by the formula 0.5mr^2. For points other than the center of mass, the parallel axis theorem can be applied, which states that the moment of inertia about a parallel axis is calculated as I = I_cm + md^2, where I_cm is the moment of inertia about the center of mass, m is the mass, and d is the distance from the center of mass to the new axis. The discussion also touches on the applicability of this theorem to 3D shapes. The conversation concludes with a reminder of the parallel axis theorem's relevance.
TheDestroyer
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As we know the moment of Inertia of a disc in the center of mass equals 0.5mr^2

My Simple question is: what is the moment of inertia of the disc at any other point? as I know there is a formula that supports the distance from the center of mass,

and is there a relation for 3D shapes?

Thanks
 
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Do you know the parallel axis theorem?

The moment of inertia for an object rotating about an axis that does not pass through its centre of mass, but which is parallel to it, is

mr^2 + (moment of inertia about an axis through the centre of mass and parallel to the other axis)

The r is the distance from the axis to the centre of mass.
 
Thank you, I know that law but this was 3 years ago, Thank you for reminding me, This post is closed!
 

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