Q. A carrier frequency of $1MHz$ and peak value of $10V$ is amplitude modulated with a signal frequency of $10\ kHz$ with peak value of $0.5\ V$. Then the modulation index and the side band frequencies respectively are
A) 0.05 and $1 \pm 0.010\ MHz$
B) 0.5 and $1 \pm 0.010\ MHz$
C) 0.05 and $1 \pm 0.005\ MHz$
D) 0.5 and $1 \pm 0.005\ MHz$
Explanation
(a) Modulation index, $\mu = \frac{A_{m}}{A_{c}} \Rightarrow \mu = \frac{0.5V}{10V} = 0.05$
The side bands frequencies are $v_{SB} = v_{c} \pm v_{m}$
$= 1 \pm 0.010\ MHz$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.