Point masses `1, 2, 3 "and" 4 "kg` are lying at the point `(0, 0, 0), (2, 0, 0), (0, 3, 0)` and `(–2, –2, 0)` respectively. The moment of inertia of this system about x-axis will be

Options

A. `43kgm^(2)`
B. `34kgm^(2)`
C. `27kgm^(2)`
D. `72kgm^(2)`

Answer

A

Explanation

Moment of inertia of the whole system about the axis of rotation will be equal to the sum of the moments of inertia of all the particles.

`therefore I=I_(1)+I_(2)+I_(3)+I_(4)`
`=0+0+27+16`
`=43kgm^(2)`