JEE Main · 2023 · 29 Jan 2023 · Shift 2 · Semiconductors

The modulation index for an A.M. wave having maximum and minimum peak to peak voltages of 14 mV and 6 mV respectively is:

Answer: (B)

Solution

The modulation index of an amplitude-modulated wave is

μ = \frac{A _{m a x} - A _{m i n}}{A _{m a x} + A _{m i n}}

. With the maximum and minimum peak-to-peak voltages

14

mV and

6

mV,

μ = \frac{14 - 6}{14 + 6} = \frac{8}{20} = 0.4

. The modulation index is

0.4

JEE Main · 2023 · 29 Jan 2023 · Shift 2 · Single correct option