Question 1

For attenuation of high frequencies we should use

Accepted Answer

Since Xc for high frequencies is low, the high frequencies are shunted to ground and are not transmitted.

Question 2

Which of the following is the indirect way of FM generation?

Accepted Answer

It generates FM through phase modulation.

Question 3

Assertion (A): Free space does not interfere with normal radiation and propagation of radio waves Reason (R): Free space has no magnetic or gravitational fields.

Accepted Answer

Since free space does not have magnetic and other fields, waves can propagate without any interference.

Question 4

If the frequency of a wave 20 Hz, the time period is

Accepted Answer

.

Question 5

Push pull amplifier is

Accepted Answer

Push pull is a power amplifier.

Question 6

Radio broadcasts are generally

Accepted Answer

Frequency modulation gives noise free reception and is used for radio broadcasts.

Question 7

Energy content of atmospheric noise

Accepted Answer

Atmospheric noise decreases as frequency is increased.

Question 8

The range of a cordless telephone is about

Accepted Answer

The range depends on quality of instrument and is about 100 m.

Question 9

VSB modulation is preferred in TV because

Accepted Answer

VSB (vestigial side band) transmission transmits one side band fully and the other side band partially thus, reducing the bandwidth requirement.

Communication Systems Questions