JEE Main 2017PhysicsCommunication SystemEasyMCQ

JEE Main 2017 — Communication System Question with Solution

JEE Main 2017 (08 Apr Online)

Question

A signal of frequency 20 kHz and peak voltage of 5 Volt is used to modulate a carrier wave of frequency 1.2 MHz and peak voltage 25 Volts. Choose the correct statement.

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Show full solutionCorrect option: C
Correct answer
CModulation index =0.2, side frequency bands are at 1220 kHz and 1180 kHz. 

Step-by-step explanation

Modulation index defines the modulated signal's ratio of maximum to minimum voltage

=VmVc=525=0.2
Carrier Frequency 1.2×103 kHz

fc=1200 kHz. 

Lower side-band frequency, f1=1200-20=1180 KHz. 

Upper band frequency,  f2 =1200+20=1220 KHz . 

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About this question

This is a previous-year question from JEE Main 2017, covering the Communication System chapter of Physics. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.