If a message signal of frequency 10 kHz and peak voltage 12 ~V is used to modulate a carrier wave of frequency 1 MHz , the modulation index is 0.6 . To make the modulation index 0.75 , the carrier peak voltage should be

Step-by-step solution

Modulation index, M= V_ peak, signal V_ peak, carrier Let's write V_ peak, carrier =V In first case, 0.6= 12 V V=20 ~V In second case, 0.75= 12 V^ V^ = 12 0.75 =16 ~V Change in peak voltage of carrier wave V=20-16=4 ~V % change = 4 20 100 %=20 %( decrement )