Four spheres of diameter 2a and mass M are placed with their centres on the four corners of a square of side b. Then moment of inertia of the system about an axis about one of the sides of the square is :-

Options

A. `(4)/(5) Ma^(2) + 2Mb^(2)`
B. `(8)/(5) Ma^(2) + 2Mb^(2)`
C. `(8)/(5) Ma^(2)`
D. `(4)/(5) Ma^(2) + 4Mb^(2)`

Answer

B

Explanation

`I= ((2)/(5) Ma^(2)) xx 2 + ((2)/(5) Ma^(2)) xx 2 + 2M b^(2)`
`= (8)/(5) Ma^(2) + 2Mb^(2)`