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Question
Find the radius of gyration of a uniform disc about an axis perpendicular to its plane and passing through its center.
Solution
M.I. of a uniform disc about an axis perpendicular to the plane and passing through its centre: I = `"MR"^2/2`
Since I = MK2
`"MR"^2/2`= MK2
`"MR"^2/(2"M")` = K2
K = `sqrt(("MR"^2)/(2"M")) = "R"/sqrt2`
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