Question

Vivid explanation of the working principle of the electric motor and as well compare it with the galvanometer stating their differences. Thanks!

Answer 1

The electric motor converts electrical energy into mechanical energy through the use of rotating magnetics fields to produce torque. By running electric current through a wire it creates a magnetic field perpendicularly to it normally in the rotor an stator. This in turn causes torque on the motor shaft allowing it to turn. By changing the poles of the magnetic fields at precise intervals this rotation can be continued indefinitely.

A galvanometer is a type of ammeter that measures electrical current through a transducer. Once again it takes in an electrical current, which in turn creates a magnetic field the coil twists due to magnetic field and pushes against a spring which moves the pointer to the correct number of amps on the dial.

The important difference between these two is that in the galvanometer the magnetic field is kept uniform and constant so the results can be accurate read. In the electric motor the magnetic field is varied in one of two ways. one of the magnetic fields is either varied in strength or the poles are reversed to keep the motor shaft rotating. Regardless of which way is chosen in the motor the field is varied in some way while the galvanometer had a constant magnetic field. One device depends on constant magnetic field while one utilizes a changing magnetic field.