Q 12-08-079JEE MainJEE Main 2023 (31 Jan, Shift 1)Easy
The amplitude of $15\sin(1000\pi t)$ is modulated by $10\sin(4\pi t)$ signal. The amplitude modulated signal contains frequency(ies) of
(A) $500\ \text{Hz}$
(B) $2\ \text{Hz}$
(C) $250\ \text{Hz}$
(D) $498\ \text{Hz}$
(E) $502\ \text{Hz}$
Choose the correct answer from the options given below:
Answer: (B) A, D and E only
Carrier: $f_c=\dfrac{1000\pi}{2\pi}=500\ \text{Hz}$; message: $f_m=\dfrac{4\pi}{2\pi}=2\ \text{Hz}$.
An AM wave contains $f_c$ and the side bands $f_c\pm f_m$: $500$, $498$ and $502\ \text{Hz}$.
Solution by Sreeraj P, M.Sc Physics