Question

(a) State what would happen to the direction of rotation of a motor if:
(i) the current were reversed
(ii) the magnetic field were reversed
(iii) both current and magnetic field were reversed simultaneously.

(b) In what ways can a motor be made more powerful?

Answer 1

(a)
(i) The direction of rotation of the motor will get reversed on reversing the direction of flow of current in the coil.

(ii) The direction of rotation of the motor will get reversed on reversing the direction of magnetic field.

(iii) The direction of rotation of the motor will not change if both current and magnetic field are reversed simultaneously.

(b) We can make a motor more powerful by following ways:

(i) If the coil is wound on a soft iron core, the strength of magnetic field increases.

(ii) By increasing the number of turns of insulated copper wire of the coil

(iii) By using a powerful electromagnet in place of permanent magnet