Two magnets of moments `M_(1)` and `M_(2)` are rigidly fixed togetherat their centres so that their axes are inclined to each other. This system is suspended ibn a magnitude field of induction `'B'` so that `M_(1)` makes an angles `theta_(1)` and `M_(2)` makes an angles `theta_(2)` with the field direction and unlike poles on either side of the field direction. The resultant torque on the rigid system is

Options

A. `B(M_(1)sintheta_(1)+M_(2)sintheta_(2))`
B. `B(M_(1)costheta_(1)+M_(2)costheta_(2))`
C. `B(M_(1)sintheta_(2)+M_(2)sintheta_(1))`
D. `B(M_(1)costheta_(2)+M_(2)costheta_(1))`

Answer

A

Explanation

Net torque

`tau=M_(1)Bsintheta_(1)+M_(2)Bsin(180-theta_(2))`