Calculating moment of inertia for a uniform rod of mass

AI Thread Summary
To calculate the moment of inertia for a uniform rod rotating about one end with an added point mass at the other end, the moments of inertia must be combined correctly. The moment of inertia of the rod is given by I = (MR^2)/3, while the point mass contributes MR^2. It is essential to ensure both calculations are relative to the same axis, utilizing the parallel axis theorem if necessary. The total moment of inertia is the sum of both contributions. Proper application of these principles will yield the correct result.
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I have a uniform rod of mass M, which rotates about one of its ends, and a point mass equal to the mass of the rod is added to the other end.

To calculate the new moment of inertia, do I just need to add the moment of inertia of the rod and that of the point mass together?

i.e. I = (MR^2)/3 + MR^2 ?

Any help would be much appreciated.
 
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Yes you add them together, but make sure you add them together with respect to the same axis. Remember the parallel axis theorum.
 
Cheers for that.
 

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