Moving coil galvanometer operates on a Permanent Magnet Moving Coil(PMMC) mechanism and was designed by the scientist D'arsnoval.

It is of two types:

(i) Suspended coil

(ii) pivoted coil type / tangent galvanometer.

Its working is based on the fact that when a current carrying coil is placed in a magnetic field, it experiences a torque that rotates the coil about its axis of suspension in such a way that the magnetic flux passing through the coil is maximum.

What is the torque acting on the coil having N-turns of area A and carrying current I placed in a radial magnetic field of strength B in a moving coil galvanometer?

NABI

torque = NABI