12th Physics 2018 Set1 Delhi Board Paper Solution
A carrier wave of peak voltage 15 V is used to transmit a message signal. Find the peak voltage of the modulating signal in order to have a modulation index of 60%.
It is given that peak voltage of carrier wave, Ac = 15V
and, Modulation index, mu = 60% = 60/100
Then, peak voltage of the modulating signal (Am) will be given by relation,
mu = Am/Ac
60/100 = Am/15V
Am = 60/100 x 15V
Am = 9V
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