A 100m long antenna is mounted on a 500 m tall building. The complex can become a transmission tower for waves with \(\lambda \).

Out of the following, which is not an essential element of a communication system?

The frequency band of FM broadcast is

The correct relation between plasma frequency v of a radio wave and electron density N of the ionosphere layer is

The fraction of world's human population using the services of internet is

What is changed in amplitude modulation?

What is the total modulation index when a carrier wave is modulated by a number of sine waves?

What is meant by attenuation and distortion?

The distance between transmitting antenna and receiving antenna at which they can see each other is called -------------

what is heterodyning?

On a particular day maximum frequency reflected from the ionosphere is 9Mhz.On another day it was found to increase by one Mhz.What is the ratio of the maximum electron density of the ionosphere on the two days.Hints: Nmax / nmax = (νc’/νc)²= 1.23

What are the limitations of amplitude modulation?

What is the frequencies used in satellite communication? What is common between these waves and light waves?

Block diagram of a receiver is shown in the figure:

(a) Identify 'X' and 'Y'.
(b) Write their functions.

A 100 MHz carrier is modulated by a 12 kHz sine wave so as to cause a frequency swing of +50kHz. Find the modulation index

Estimate the fastest bit rate capable of being carried by light of wavelength 1.3 \(\mu m\). How many phone calls could be carried at this bit rate? Bandwidth of optical fibre = 2 GHz.

Mohan went to the market to purchase a TV set. He got confused with so many features and functions of electronic appliances. He took the help of his friend Sohan, a science student.Sohan explained him about the communication system, digital and analog signals. This knowledge proved of great help to Mohan in purchasing a colour TV.
Read the above passage and the answer the following questions:
(i)  What do you mean by the term communication?
(ii) Which type of signals are better?
(iii) What type of nature Sohan has?
(iv)What is the minimum number of communication satellites required for global communication coverage?

By what percentage will the transmission range of a T.V. tower be affected when the height of the tower is increased by 21%?