Q130 / 150 · MHT CET 2020 (13 Oct Shift 1) · Physics
A signal of frequency $3 \mathrm{kHz}$ is amplitude modulated on a carrier wave of frequency
$2 \cdot 5 \mathrm{MHz}$. The upper and lower sideband frequencies in the resultant signal are
- A$2500 \mathrm{kHz}, 2503 \mathrm{kHz}$
- Correct answerB$2503 \mathrm{kHz}, 2497 \mathrm{kHz}$
- C$2 \cdot 5 \mathrm{MHz}, 3 \mathrm{kHz}$
- D$5 \cdot 5 \mathrm{MHz}, 0 \cdot 5 \mathrm{MHz}$
Solution
$\begin{aligned} f_{R}=f_{C}+f_{m} &=2500 \mathrm{KHz}+3 \mathrm{kz} \\ &=2503 \mathrm{KHz} \\ f_{R}=f_{C}-f_{m} &=2500 \mathrm{kHz}-3 \mathrm{kHz} \\ &=2497 \mathrm{kHz} \end{aligned}$
Hence, the correct answer is option: 'B'.