# +2 Physics - Communication Systems - Part 2

Continuing our collection of objective type questions in +2 Physics, questions from 9 -18 are provided in this post, covering the Communication Systems chapter.

9) A ------------ radio wave is used to carry the audio signal.

10) The process of changing amplitude or frequency of the carrier wave in accordance with the intensity of the signal is ---------.

a) Modulation
b) Reception
c) Amplification
d) Demodulation

11) When the amplitude of high frequency carrier wave is changed in accordance with the intensity of the signal, the process is called ----------

a) frequency modulation
b) Pulse code modulation
c) Phase modulation
d) Amplitude Modulation

12) In amplitude modulation, which of the following is constant?

a) Amplitude
b) Frequency
c) Phase
d) Both Frequency and Phase.

13) Modulation factor is defined as the ratio of

a) Signal amplitude to Carrier amplitude
b) Carrier amplitude to Signal amplitude
c) Carrier amplitude to twice signal amplitude
d) twice signal amplitude to carrier amplitude

14) For effective modulation, the degree of modulation should never exceed

a) 1
b) 100%
c) 75%
d) 0%

15) The frequency of an FM transmitter without signal input is called -------

a) resting frequency
b) centre frequency
c) both (a) and (b)
d) cut off frequency

16) The total variation in frequency from the lowest to the highest is called --------

a) frequency swing
b) carrier swing
c) variational swing
d) Modulation swing.

17) The bandwidth used in phase modulation is ----------- than that of FM.

a) equal
b) greater
c) smaller
d) greater than or equal

18) A transmitting Antenna converts electrical signal to -----------

a) electromagnetic energy
b) Mechanical energy
c) Kinetic energy
d) Potential energy