Two circular discs are of same thickness. The diameter of `A` is twice that of `B`. The moment of inertia of `A` as compared to that of `B` is

Options

A. twice as large
B. four times as large
C. `8` times as large
D. `16` times as large

Explanation

`(M_(A))/(M_(B))=(pi(2r)^(2))/(pir^(2))=4, M_(A)=4 M_(B)`
`(I_(A))/(I_(B))=(M_(A)(2r)^(2))/(M_(B)r^(2))=16`