# NCERT Solutions for Class 12 Physics Chapter 15 Communication Systems

NCERT Solutions for Class 12 Physics Chapter 15 Communication Systems are available here in PDF Format. So, Candidates of state and central boards like UP, MP, Gujarat, Uttarakhand, CBSE should follow them to ace up your preparation. These solutions are specially designed in both Hindi and English mediums to make it easy while learnings.

You all can avail NCERT Class 12 Physics Ch 15 Solutions in PDF Download links for easy download & access offline. The smartest way to get familiar with the concept of Communication systems by preparing with the NCERT Solutions material. These prevailing NCERT Solutions covers the practice problems so that you can understand all the concepts easily.

## Class 12 Physics NCERT Solutions Chapter 15 Communication Systems

In this chapter, the 12th class students will come to learn about the communication systems concept. The introduction of the communication system is nothing but sending and receiving the data and information from one place to another. This last chapter in NCERT Solutions Class 12 Physics textbook talks all about covered 10 topics of communication systems.

Besides, this chapter goes in detail about the elements called the channel, the transmitter, and the receiver. Also, they will study some other important concepts like the bandwidth of various transmission mediums, the bandwidth of signals, amplitude modulation, the necessity of modulation, propagating electromagnetic waves, etc.

 Class 12 Subject Physics Book Physics Chapter Number 15 Chapter Name Communication Systems

### NCERT Exercise Questions with Solutions of 12th Physics Ch 15 PDF

These NCERT Solutions for Class 12 Physics Chapter 15 aims to introduce the learners to the communication concept. Besides, an explanation of each and every question in NCERT Solutions PDF includes charts, diagrams, examples, and illustrations to understand the concept in an interesting and easy to learn.

Question 1.
At which of the following frequency/frequencies the communication will not be reliable for a receiver situated beyond horizon:
(a) 10 kHz
(b) 10 MHz
(c) 1 GHz
(d) 1000 GHz
(b) is correct. Here (c) and (d) frequencies have high penetration power so the earth will absorb them. Radiation (a) of 10 kHz will suffer from the problem of size of antenna.

Question 2.
Frequencies in the UHF range normally propagate by means of
(a) ground waves
(b) sky waves
(c) surface waves
(d) space waves.
(d) space waves.

Question 3.
Digital signals (i) do not provide a continuous set of values, (ii) represent values as discrete steps, (Hi) can utilize only binary system, and (iv) can utilize decimal as well as binary system. Which of the following options is true :
(a) Only (i) and (ii).
(b) Only (ii) and (iii).
(c) Only (i), (ii) and (iii), but not (iv).
(d) AH the above (i) to (iv).
(c) is correct because decimal system is concerned with continuous values (i) to (iii).

Question 4.
Is it necessary for a transmitting antenna to be at the same height as that of the receiving antenna for line- of-sight communication ? A TV transmitting antenna is 81 m tall. How much service area can it cover if the receiving antenna is at the ground level?
For line-of-sight communication it is necessary that the transmitting antenna and receiving antenna should be eye to eye but it is not necessary that they should be at the same height. Question 5.
A carrier wave of peak voltage 12 V is used to transmit a message signal. What should be the peak voltage of the modulating signal in order to have a modulation index of 75% ? Question 6.
A modulation signal is a square wave as shown in figure. The carrier wave is given by
C(t) = 2 sin(8πt) V (a) Sketch the amplitude modulated waveform.
(b) What is the modulation index ?  Accordingly, the amplitude modulated waveform is shown ahead:

Question 7.
For an amplitude modulated wave, the maximum amplitude is found to be 10 V while the minimum amplitude is found to be 2 V. Determine the modulation index μ.What would be the value of μ if the minimum amplitude is zero V ? Question 8.
Show that if a device is available which can multiply two signals, then it is possible to recover the modulating signal at the receiver station. 