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A cavity of radius b is made in a disc o...

A cavity of radius b is made in a disc of mass M, radius R, as ahown in fig. Find the new COM-

A

`(-b^(2))/(R+b)`

B

`(-b^(2))/(R-b)`

C

`(-R)/(2R+b)`

D

`(-R)/(3R+b)`

Text Solution

Verified by Experts

The correct Answer is:
A
`x_(CM)=(M(0)-(Mb^(2))/(R^(2))(R-b))/(M-(Mb^(2))/R^(2))`
`=-(b^(2))/(R+b)`
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