* A thin rod of length L and mass m rotates around an axis perpendicular to the rod. passing through the rod’s left end Treat the rod as an object made up of five rods of length L/5. Derive an expression for the rotational inertia of this five-piece object around the same axis, assuming each piece is a point-like object with mass m/5. Compare your result with the expression for the rotational inertia of the one-piece rod
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