Question

What is a solar cell? State two uses of solar cells. State whether a solar cell produces a.c. or dc. Give one disadvantage of using a solar cell.

Answer 1

A solar cell is an electrical device that converts light energy directly into electricity with the help of photovoltaic effect. Solar cells are usually made from semiconductors like silicon and gallium with some impurity added to it. When sunlight is made incident on a solar cell, a potential difference is produced between its surface, due to which a current flows in the circuit connected between the opposite faces of the semiconductor.

Two uses of solar cells are as listed below:

1. They do not require maintenance and last over a long period of time at zero running cost.
2. They are very useful for remote, inaccessible and isolated places where electric power lines cannot be laid. A solar cell produces d.c. (direct current).

One disadvantage of solar cell is listed below:

(i) The initial cost of a solar panel is sufficiently high.