Q144 / 150 · MHT CET 2020 (19 Oct Shift 2) · Physics
A carrier wave of peak voltage 16 volt is used to transmit a signal. If the
modulation index is $75 \%$, the peak voltage of the modulating signal is
- A6 volt
- B24 volt
- C18 volt
- Correct answerD12 volt
Solution
A carrier wave of peak voltage $16 \mathrm{~V}$ is used to transmit a signal. If the modulation index is $75 \%$, the peak voltage of the modulating signal is $12 \mathrm{~V}$.
Explanation:
Modulation Index
$(\mathrm{MI})=\frac{\text { Peak voltage of modulating signal }\left(\mathrm{V}_{\mathrm{m}}\right)}{\text { Peak voltage of carrier } \operatorname{signal}\left(\mathrm{V}_{\mathrm{C}}\right)}$
Given, $\mathrm{Ml}=75 \%$ and $\mathrm{V}_{\mathrm{C}}=16 \mathrm{~V}$
$\therefore \mathrm{V}_{\mathrm{m}}=\mathrm{MI} \times \mathrm{V}_{\mathrm{c}}=\frac{75}{100} \times 16=12 \mathrm{~V}$
Hence, the correct answer is option: 'D'.