The moment of inertia of a cube of mass m and side a about one of its edges is equal to

Options

A. `(2)/(3) ma^(2)`
B. `(4)/(3)ma^(2)`
C. `3ma^(2)`
D. `(8)/(3)ma^(2)`

Answer

A

Explanation

From theorem of perpendicular axes, we have
`I=I_(c)+m((a)/(sqrt(2)))^(2)=((ma^(2))/(12)+(ma^(2))/(12))+(ma^(2))/(2)=(2)/(3)ma^(2)`.