A Carrier Wave of Peak Voltage 12 V is Used to Transmit a Message Signal. What Should Be the Peak Voltage of the Modulating Signal in Order to Have a Modulation Index of 75%? - Physics


A carrier wave of peak voltage 12 V is used to transmit a message signal. What should be the peak voltage of the modulating signal in order to have a modulation index of 75%?



Amplitude of the carrier wave, Ac = 12 V

Modulation index, m = 75% = 0.75

Amplitude of the modulating wave = Am

Using the relation for modulation index:

`m = A_m/A_c`

`:. A_m = mA_c`

`= 0.75 xx 12 = 9 V`

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Chapter 15: Communication Systems - Exercise [Page 530]


NCERT Physics Class 12
Chapter 15 Communication Systems
Exercise | Q 5 | Page 530


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(i) (ii) (iii) (iv)

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