Question

Write a short note on surface wave propagation of electromagnetic waves.

Answer 1

Definition :
When the electromagnetic waves (radiowaves) from the transmitting antenna propagate along the surface of
the earth so as to reach the receiving antenna, the wave propagation is called ground wave propagation
(surface wave propagation). [1 mark]

Explanation :

(i) Ground waves are the radiowaves which propagate along the surface of the earth.

(ii) There is loss of power in a signal during its propagation on the surface of the earth due to partial
absorption of energy by ground. Hence ground wave propagation is suitable for low frequency and
medium frequency. It is used for local broadcasting.

(iii) Ground wave propagation is possible only when the transmitting and receiving antenna are close to
the earth’s surface.