Auto mechanics Paper 2 WASSCE (PC), 2017

Question 1

 

(1)(a) State two advantages of alternator over generator.
(b) List three parts of a generator.
(c) State two means of charging a lead-acid battery.
(d) How many cells are in a 12V battery?
(e) State the Ohm’s Law.

Observation

 

The candidates that attempted this question did well. However, a few of them could not satisfactorily answer questions 1 (a) and (b). Below are the solutions of the poorly answered questions.

 

Solution

(a)  Advantages Alternator over Generator
-    It has lower cost of maintenance.
-   It has much higher operating speed due its smaller pulley.
-   It gives better power output at both low and high speeds.
-   It is lighter in weight.
-   It is smaller, hence consumes less space.
-   It has simpler control system.
-   It has greater reliability.

(b)  Parts of Generator
-   Armature
-   Commutator
-   Field coils or pole windings
-   Yoke or casing
-   Brushes
-   Bushes or bearings
-   End bracket
-   Brush holder or spring
-   Spindle end
-   End plate
-   Through bolts