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Question
Answer in brief:
A uniform disc and a hollow right circular cone have the same formula for their M.I. when rotating about their central axes. Why is it so?
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Solution
A uniform disc and a hollow right circular cone have the same formula for their moment of inertia.
`"MI" = 1/2mr^2`
This is due to the fact that when a hollow right circular cone is sliced along its slanting side and the metal is stretched out, the cone's surface becomes a circle. This shape is similar to that of a disc, which is a circular as well. As a result, they both share the same moment of inertia formula.
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