Set 1 MCQ Questions & Answers Detailed Explanation

Question : 1

Light Emitting Diode (LED) converts

a) electrical energy into light energy

b) thermal energy into light energy

c) light energy into electrical energy

d) mechanical energy into electrical energy

Question : 2

At absolute zero, Si acts as

a) metal

b) insulator

c) non-metal

d) None of these

Question : 3

Space wave propagation is:

1. tropospherical propagation
2. sky wave propagation
3. line of sight propagation

a) 1 and 3

b) 2 only

c) 1 only

d) 2, 3 and 4

Question : 4

The service area of space wave communication increases by –

a) Decreasing the height of receiving antenna

b) Increasing the height of both transmitting and receiving antenna

c) Increasing the height of transmitting antenna

d) Decreasing the distance between transmitting and receiving antenna

Question : 5

The process of superimposing signal frequency (i.e., audio wave) on the carrier wave is known as

a) Reception

b) Modulation

c) Transmission

d) Detection