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A uniform disc of mass M and radius R is...


A uniform disc of mass `M` and radius R is pivoted about the horizontal axis through its centre `C` A point mass m is glued to the disc at its rim, as shown in figure. If the system is released from rest, find the angular velocity of the disc when `m` reaches the bottom point B.

Text Solution

Verified by Experts

From conservation of mechanical energy decrease in gravitaional `PE=` increase in rottional KE
or `mg(R)=[(1)/(2)MR^(2)+mR^(2)]((1)/(2)omega^(2))`
or `omega=sqrt((4mg)/((2m+M)R))`
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