Question 3
- State two sources by which a battery can be re-charged.
- State the principle of operating ;
- solar cell;
- accumulator.
Observation
The expected answers were;
-
(a) (i) Photo voltaic / solar cell
(ii) DC source / Rectifier
(iii) AC-DC converter
(b) (i) Solar Cell:
This is a solid state electrical device (p-n junction) that converts light energy directly into electricity (D.C) using the photovoltaic effect.
(ii) Accumulator:
This is an energy storage device which accepts energy, stores energy and releases the energy when needed. It uses two dissimilar metals dipped into an electrolyte.
Many candidates who attempted this question stated one of the sources correctly while they mentioned function rather than operating principle.