Three point masses `m_(1), m_(2)` and `m_(3)` are located at the vertices of an equilateral triangle of side `alpha`. What is the moment of inertia of the system about an axis along the altitude of the triangle passing through `m_(1)?`

Options

A. `(m_(1)+m_(2))(a^(2))/4`
B. `(m_(2)+m_(3))(a^(2))/4`
C. `(m_(1)+m_(3))(a^(2))/4`
D. `(m_(1)+m_(2)+m_(3))(a^(2))/4`

Answer

B

Explanation

`I=m_(1)(a/2)^(2)+m_(2)(a/2)^(2)`