Question

If a wave is modulated by two waves. One of them has modulation index equal to 0.75 and other has 0.2, the total modulation index will be ________

(a) 0.67

(b) 0.58

(c) 0.77

(d) 0.35

I have been asked this question in a national level competition.

Asked question is from Power Calculation topic in division Amplitude Modulation of Analog Communications

Answer 1

The correct option is (c) 0.77

Explanation: Given that m1 = 0.75 and m2 = 0.2. Total modulation index will be equal to  By substituting values we have  which is equal to 0.77.