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Question
Calculate the moment of inertia of a uniform disc of mass 10 kg and radius 60 cm about an axis perpendicular to its length and passing through its center.
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Solution
Given, m = 10 kg
r = 60 cm
r = 60 × 10-2 m
l = ?
Moment of inertia of a uniform disc
l = `"mr"^2/2`
`= (10 xx (60 xx 10^-2)^2)/2`
`= (10 xx 3600 xx 10^-4)/2`
= 1.8 kgm2
Moment of inertia of a uniform disc is 1.8 kg m2.
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