Question

Carrier wave and modulating wave voltages increase by 1% and 3%. Find change in modulation index.

• A. \(-2%\)
• B. \(4%\)
• C. \(2%\)
• D. \(-4%\)

Hint:

Modulation index is ratio of modulating to carrier amplitude.

Answer 1

The Correct Option is A

Modulation index: \[ \mu = \frac{V_m}{V_c} \Rightarrow \frac{1.01}{1.03} \approx 0.9806 \Rightarrow \text{Change} = (0.9806 - 1) \times 100 \approx -2% \]