# Problems of AM MCQ’s

This set of Analog Communication Multiple Choice Questions & Answers (MCQs) focuses on “Problems of AM”.

1. A 400W carrier wave is modulated to a depth of 65%. Find the total power of modulated wave?
a) 512.5W
b) 493W
c) 484.5W
d) 609.6W

2. Inductance and capacitance of a line is 0.8 μHm and 32 pFm. Find Z0?
a) 158
b) 166
c) 143
d) 127

3. If the modulating frequency of a carrier wave varies between 700Hz and 7KHz, find it’s bandwidth?
a) 10 KHz
b) 23 KHz
c) 17.3 KHz
d) 12.6 KHz

4. Find VSWR of a line having maximum and minimum value equals to 120mV and 40mV respectively?
a) 3
b) 2
c) 1
d) 4

5. If average power of a transmitter is 4kW and maximum power is 20000KW. What is its duty cycle?
a) 2 x 10-3
b) 2 x 10-4
c) 3 x 10-3
d) 0.05

6. ________ microphones works on piezoelectric effect.
a) Crystal
b) Carbon
c) Moving coil
d) Condenser

7. A 1000 KHz carrier is modulated with 300 Hz, 8000 Hz and 2 KHz waves. Determine the frequencies whose chances of occurring in output is least?
a) 1000 KHz
b) 1002 KHz
c) 998 KHz
d) 999.2 KHz

8. The voltage and electric current of a line are respectively 5kV and 1000μA. Find its power?
a) 12W
b) 13W
c) 5W
d) 10W

9. If modulation index of an AM wave is increased from 1.5 to 2, then the transitted power ________
a) remains same
b) increases by 20%
c) increases by 41%
d) increases by 50%