Class 12 Physics - Chapter 15: Communication Systems Physics MCQ Questions

35 Questions 70 Minutes

Progress: 0 / 35

Your Class 12 Physics Study Path

Question 1

(a) 9.5 to 2.5 GHz

A (e) 3.7 to 4.2 MHz

B 840 to 935 MHz

C 3.7 to 4.2 GHz

D 896 to 901 MHz

Question 2

(a) 2010 kHz, 1990 kHz

A (e) 2200 kHz, 1800 kHz

B 2100 kHz, 1900 kHz

C 2010 kHz, 2000 kHz

D 2000 kHz, 1990 kHz

Question 3

(a) 8 kHz

A (e) 400 kHz

B 3.8 kHz

C 7.6 kHz

D 4 kHz

Question 4

(a) its low frequency

A (e) both its low frequency and high intensity

B smaller antenna

C its high intensity

D curvature of earth

Question 5

(a) Satellite cable communication

A (e) Fax transmission

B AM radio transmission

C FM radio transmission

D Television transmission

Question 6

(a) receiver and modulator

A (e) amplifier and transmitter

B receiver and amplifier

C receiver and transmitter

D receiver and transducer

Question 7

(a) Noise – Unwanted signals

A (e) Attenuation – Strengthening of signal

B Demodulation – Retrieval of information

C Transducer – Energy converter

D Repeater – Communication satellite

Question 8

(a) space waves

A (e) sky waves, ground waves and space waves

B both sky and ground waves

C sky waves

D ground waves

Question 9

(a) modulating device only

A (e) receiving device

B transmitting device

C modulating and demodulating device

D demodulating device only

Question 10

(a) is doubled

A (e) increases 16 times

B is quadrupled

C remains constant

D is halved

Question 11

(a) 1 – 100 MHz

A (e) 10 – 1000 MHz

B 800 – 950 MHz

C 1000 – 2000 MHz

D 100 – 200 MHz

Question 12

(a) 4 : 1

A (e) 1 : 4

B 2 : 1

C 1 : 2

D 1 : 1

Question 13

(a) ground waves

A (e) sky waves

B space waves

C direct waves

D surface waves

Question 14

(a) AM detection is carried out using a rectifier and an envelop detector

A (e) Detection is the process of recovering the modulating signal from the modulated carrier wave.

B Facsimile (FAX) scans the contents of the document to create electronic signals.

C Modulation index p is kept â‰¥ 1, to avoid distortion.

D Pulse position denotes the time of rise or fall of the pulse amplitude.

Question 15

(a) (sqrt {2Rh})

A (e) (sqrt {Rh})

B (sqrt {8Rh})

C (sqrt {6Rh})

D (sqrt {4Rh})

Question 16

(a) Analog signals provide a continuous set of values

A (e) Digital signals can utilize decimal as well as binary systems

B Digital signals can be processed by logic gates

C Analog signals cannot utilize the binary system

D Digital signals represent values as discrete steps

Question 17

(a) (frac { 1 }{5})

A (e) (frac { 2 }{3})

B (frac { 2 }{5})

C (frac { 3 }{2})

D (frac { 1 }{3})

Question 18

(a) 6.4 m

A (e) 25.6 m

B 16 m

C 3.2 m

D 12.8 m

Question 19

(a) 540- 1600 kHz

A (e) 174 – 216 MHz

B 54 – 72 MHz

C 3.7-4.2 GHz

D 88 – 108 MHz

Question 20

(a) (frac { l }{Î»})

A (e) (frac { l }{âˆšÎ»})

B (frac { l^2 }{Î»})

C (frac { l }{Î»^2})

D (frac { l^2 }{Î»^2})

Question 21

(a) 1280 m

A 1050 m

B 79 m

C 1560 m

D 1125 m

Question 22

(a) space waves, sky waves, ground waves

A (e) sky waves, space waves, ground waves

B ground waves, sky waves, space waves

C sky waves, ground waves, space waves

D space waves, ground waves, sky waves

Question 23

The power radiated by a linear antenna of length l at wavelength Î» is

A directly proportional to Î»Â²

B inversely proportional to l

C inversely proportional to Î»

D directly proportional to l

Question 24

(a) 636 kHz, 630 kHz

A (e) 6 kHz, 630 kHz

B 1260 kHz, 630 kHz

C 1260 kHz, 6 kHz

D 12 kHz, 6 kHz

Question 25

(a) twice the audio signal frequency

A (e) sum of audio signal frequency and carrier wave frequency

B twice the carrier wave frequency

C thrice the carrier wave frequency

D thrice the audio signal frequency

Question 26

(a) is a part of the antenna

A (e) converts physical variable into corresponding variations in the electrical signal

B detects the incoming signal

C converts audio signals into video signals

D is a combination of a receiver and a transmitter

Question 27

(a) FM radio

A (e) telephony

B internet

C television

D standard FM radio

Question 28

(a) (sqrt{R(h_T+h_R)})

A (e) (sqrt{2Rh_T}) + (sqrt{Rh_R})

B (sqrt{2Rh_T}) + (sqrt{2Rh_R})

C (sqrt{Rh_T}) + (sqrt{2Rh_R})

D (sqrt{2R/(h_T+h_R)})

Question 29

(a) 1 kHz to 10 kHz

A (e) 3 GHz to 30 GHz

B 100 kHz to 1 MHz

C 3 to 30 kHz

D 3 to 30 MHz

Question 30

(a) PAM

A (e) PCM

B FM

C PPM

D PWM

Question 31

(a) 0.8

A (e) 0.4

B 0.2

C 0.5

D 0.6

Question 32

(a) 0.05 and 1 Â± 0.010 MHz

A (e) 0.05 and 1 Â± 0.100 MHz

B 0.5 and 1 Â± 0.005 MHz

C 0.05 and 1 Â± 0.005 MHz

D 0.5 and 1 Â± 0.010 MHz

Question 33

(a) Ground wave propagation is for high frequency transmission

A (e) Very high frequency waves cannot be reflected by the ionospheric layers

B Space wave is used for satellite communication

C Space wave is of high frequency and is suitable for line of sight communication

D Sky wave propagation is facilitated by ionospheric layers

Question 34

(a) 1.56 Ã— 10⁶ kmÂ²

A (e) 1.56 Ã— 10⁴ kmÂ²

B 1.56 Ã— 10⁹ kmÂ²

C 5.6 Ã— 10¹⁰ kmÂ²

D 5.6 Ã— 10Â³ kmÂ²

Question 35

(a) 56%

A (e) 60%

B 48%

C 50%

D 30%

Related Student Tools

P0 academic

Grade Calculator

Convert marks into grade bands with transparent thresholds.

P0 academic

Marks Percentage Calculator

Calculate exam or subject-wise marks percentage.

P0 academic

Percentage Calculator

Calculate percentage from obtained marks and total marks.

Keep learning

Discover More on SaralStudy

Explore all articles

Latest Blogs

Fresh educational articles and updates.

Popular Blogs

Most-read articles from SaralStudy.

Quick & Popular Links

Fast access to frequently used study resources.

Quick Links

NCERT Sample Papers Study Planner and Calculators NCERT Books CBSE Syllabus Previous Year Question Papers CBSE Board

What Students Are Viewing

Recently viewed articles based on SaralStudy activity.

Class 12 Physics - Chapter 15: Communication Systems Physics MCQ Questions

Your Class 12 Physics Study Path

(a) 9.5 to 2.5 GHz

(a) 2010 kHz, 1990 kHz

(a) 8 kHz

(a) its low frequency

(a) Satellite cable communication

(a) receiver and modulator

(a) Noise – Unwanted signals

(a) space waves

(a) modulating device only

(a) is doubled

(a) 1 – 100 MHz

(a) 4 : 1

(a) ground waves

(a) AM detection is carried out using a rectifier and an envelop detector

(a) (sqrt {2Rh})

(a) Analog signals provide a continuous set of values

(a) (frac { 1 }{5})

(a) 6.4 m

(a) 540- 1600 kHz

(a) (frac { l }{Î»})

(a) 1280 m

(a) space waves, sky waves, ground waves

The power radiated by a linear antenna of length l at wavelength Î» is

(a) 636 kHz, 630 kHz

(a) twice the audio signal frequency

(a) is a part of the antenna

(a) FM radio

(a) (sqrt{R(h_T+h_R)})

(a) 1 kHz to 10 kHz

(a) PAM

(a) 0.8

(a) 0.05 and 1 Â± 0.010 MHz

(a) Ground wave propagation is for high frequency transmission

(a) 1.56 Ã— 106 kmÂ²

(a) 56%

Practice Complete!

Related Student Tools

Grade Calculator

Marks Percentage Calculator

Percentage Calculator

Students Also Read

Discover More on SaralStudy

Latest Blogs

Popular Blogs

Quick & Popular Links

Quick Links

Popular Study Links

What Students Are Viewing

(a) 1.56 Ã— 10⁶ kmÂ²