Answer:

a) An electric motor converts electrical energy into mechanical energy.

Working: The coil ABCD is horizontal. The current enters the carbon brush P and the half ring X commutator. The coil current leaves the coil through the ring Y and brush Q. The magnetic field runs from the N to S poles. The anticlockwise movement of the coil is caused by the Fleming left hand rule.

The current is cut off when the brushes P and Q are vertical. When the current stops, the coil continues to revolve due to its momentum. Left and right side CD and AB. The coil changes shape as the current changes direction.

b) Commercial electric motors:

The coil is wound on a soft iron to boost the magnetic field strength, making the electric motor powerful.

ii) insulated copper wire with many turns

ii) an electromagnet replaces a permanent magnet