In the figure shown, find out centre of mass of a system of a uniform circular plate of radius `3R` from O in which a hole of radius R is cut whose centre is at `2R` distance from the centre of large circular plate

Options

A. `R//4`
B. `R//5`
C. `R//2`
D. none of these

Answer

A

Explanation

`bar(x)=(m_(1)x_(1)+(-m_(2))x_(2))/(m_(1)+(-m_(2)))`
`=(A_(1)x_(1)+(-A_(2))x_(2))/(A_(1)+(-A_(2)))`
`A_(1)=pi(3R)^(2),A_(2)=pi R^(2)`
`x_(1)=O,x_(2)=2R`
`:. Bar(x)-R//4`