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In an AM signal, the greatest peak-to-peak voltage observed is 24 mV and the least peak-to-peak voltage observed is 8 mV. What is the modulation index?

1. 10%
2. 20%
3. 25%
4. 50%

Correct answer: 50%

Solution

The modulation index in AM signals is calculated as the ratio of the peak-to-peak voltage of the modulating signal to the peak-to-peak voltage of the carrier signal. In this case, the difference between the greatest and least peak-to-peak voltages indicates the modulation depth, leading to a modulation index of 50%.

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