- #1
Dethrone
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Homework Statement
I need to derive the moment of inertia of a thin rod with its axis of rotation at the end of the rod. http://en.wikipedia.org/wiki/List_of_moments_of_inertia
The third one.
Homework Equations
I = mr^2
The Attempt at a Solution
I completely understand how the moment of inertia is mL^2/3, but what I don't understand is why linear density is used. M/L. Shouldn't it be volume density, or area density at the very least since a thin rod is 3D?