Observation

    The expected answers were;

(a) Definition of an alternator

(1) An alternator is a device that receives the mechanical energy transferred from the engine through a grooved drive belt on a pulley arrangement. Through electromagnetic induction, the alternator changes this mechanical energy into electrical energy. The alternating current generated is converted into direct current by a rectifier, a set of diodes which allow current to pass only in one direction.

(2) The alternator works together with the battery to supply power to the vehicle.

(b) How alternator works with the battery The rotation of the engine drives the alternator, forcing electrical energy (current) into a battery, where it is stored as chemical energy. The chemical energy of the battery is changed back to electrical energy when it supplies current to the starter motor and accessories. The cycle repeat itself as the engine's mechanical energy again drives the alternator to recharge the battery so it can supply more current to the starter when needed.

(c) Parts of an alternator

(1) Slip rings

(2) Bearing

(3) housing

(4) Heat sink

(5) Diodes

(6) Pulley

(7) Through bolt

(8) Fan

(9) Stator core

(10) Stator winding

(11) Rotor

(12) Carbon brushes

(13) Voltage regulator

(14) Bushing

The candidates were required to define an alternator, explain how an alternator works together with a battery to supply power to a vehicle, list three parts of an alternator. It was reported that, the candidates did very well in this question.