The moving coil of a galvanometer 4 cm long and 1.5 cm wide, made of 200 turns of thin wire, works in a magnetic field with induction of 0.1 T. The plane of the coil is parallel to lines of induction. Find the torque acting on the coil when a current of 1 mA flows in it.

Answer

`1.2 xx 10^(-5) N.m. `

Explanation

The magnetic moment of the moving coil is `p_m= w//S,` while the torqlie is `M =p_mB,` since in our problem `alpha= 1//2.`