# Communication Systems MCQs Mock Test of Class 12th Physics

Welcome to your Communication Systems MCQs Mock Test of Class 12th Physics

1.
Q1. An antenna is:

2.
Q2. An example of point to point mode of communication is

3.
Q3. Audio signal cannot be transmitted because

4.
Q4. The modulation index in amplitude modulation is:

5.
Q5. The wavelength of a wave of frequency 10 kHz is:

6.
Q6. The frequency band used in the downlink of satellite communication is

7.
Q7. How many elements are essential for any communication system?

8.
Q8. The term channel is used to indicate

9.
Q9. The audio frequencies range from:

10.
Q10. A carrier frequency of 1 MHz and peak value of 10 V is amplitude modulated with a signal frequency of 10 kHz with peak value of 0.5 V. Then the modulation index and the side band frequencies respectively are

11.
Q11. Which of the following is the purpose of the transmitter?

12.
Q12. The range of frequency bands used for television VHF service is

13.
Q13. The term used “to collect the information about an object and a place without physical contact” is called :

14.
Q14. 1000 kHz carrier wave is amplitude modulated by the signal frequency 200 – 4000 Hz. The channel width of this case is

15.
Q15. Which among the following can be an input to a transmitter?

16.
Q16. Wave obtained on superimposition of audible frequency e.m. wave is known as

17.
Q17. Who undertook the first space walk and in which year?

18.
Q18. If the TV telecast is to cover a radius of 120 km (given the radius of the earth = 6400 km), the height of the transmitting antenna is

19.
Q19. Which of the following is the reason for signal distortion?

20.
Q20. Which of the following is drawback of amplitude modulation?

21.
Q21. Which of the following is not transducer?

22.
Q22. The mobile telephones operate typically in the range of

23.
Q23.What is the function of the receiver?

24.
Q24. In FM, when frequency deviation is doubled, then

25.
Q25. The space waves which are affected seriously by atmospheric conditions are:

26.
Q26. The waves that are bent down by the ionosphere are

27.
Q27. Find the odd one out.

28.
Q28. In PCM if the transmission path is very long

29.
Q29. Who undertook the first space walk and in which year?

30.
Q30. The term used “to collect the information about an object and a place without physical contact” is called :

31.
Q31. The velocity of electromagnetic wave is:

32.
Q32. The wavelength of a wave of frequency 10 kHz is:

33.
Q34. The area served by an antenna of height 100 m is:

34.
Q33. The audio frequencies range from:

35.
Q35. Which of the following is not transducer?

36.
Q36. The space waves which are affected seriously by atmospheric conditions are:

37.
Q37. An antenna is:

38.

39.
Q39. The modulation index in amplitude modulation is:

40.
Q40. The output of a digital computer is an example of:

41.
Q41. Name the man who was first to place his foot on the moon and in which year:

42.
Q42. A microphone converts:

43.
Q43. A loudspeaker converts:

44.
Q44. The sound produced by a tuning fork is a sort of:

45.
Q45. The length of a half wave dipole at 30 mega-hertz is:

46.
Q46. In space communication, the sound waves can be sent from one place to another:

47.
Q47. The output of a digital computer is an example of:

48.