Q 12-08-200JEE MainJEE Main 2019 (10 Apr, Shift 1)Easy
A message signal of frequency $100\ \text{MHz}$ and peak voltage $100\ \text{V}$ is used to execute amplitude modulation on a carrier wave of frequency $300\ \text{GHz}$ and peak voltage $400\ \text{V}$. The modulation index and difference between the two side band frequencies are:
Answer: (B) $0.25;\ 2\times10^8\ \text{Hz}$
Modulation index $= \dfrac{A_m}{A_c} = \dfrac{100}{400} = 0.25$.
Side bands are at $f_c \pm f_m$, so they differ by $2f_m = 200\ \text{MHz} = 2\times10^8\ \text{Hz}$.
Solution by Sreeraj P, M.Sc Physics