In a moving coil galvanometer, torque is controlled by a ___________.

Complete the sentence with the correct option.

 

A moving coil galvanometer is a device that is used to measure and detect a small amount of electric charge. It is based on the fact that when a current-carrying rectangular coil is placed in a magnetic field it experiences a torque.

The magnetic torque NIAB tends to rotate the coil of the galvanometer. Spring provides a counter torque $k\phi$ that balances the magnetic torque NIAB; resulting in a steady angular deflection $\phi$