Four point masses each of value m, are placed at the corners of a square ABCD of side `l`, The moment of inertia of the system about an axis passing throught A and parallel to BD is

Options

A. `3m l^(2)`
B. `ml^(2)`
C. `2ml^(2)`
D. `sqrt(3)m I^(2)`

Answer

A

Explanation

Moment of inertia of system
`I= I_(A) + I_(B) + I_(C)+ I_(D)`
`rArr I=0 + m(AO)^(2) + m(AO)^(2) + m(AC)^(2) rArr I =m(l/sqrt(2))^(2) + m(l/sqrt(2))^(2) + m(sqrt(2)l)^(2))`
`=3ml^(2)`