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The maximum amplitude of an A.M. wave is found to be 15 V while its minimum amplitude is found to be 3 V. What is the modulation index?

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प्रश्न

The maximum amplitude of an A.M. wave is found to be 15 V while its minimum amplitude is found to be 3 V. What is the modulation index?

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उत्तर

Modulation index `mu,`

= `(A_(max) - A_(min))/(A_(max) + A_(min)`  .....(A = amplitude of modulated wave)

∴ `mu = (15 - 3)/(15 + 3) = 12/18 = 2/3`.

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अध्याय 15: Communication Systems - Exercise [पृष्ठ १०२]

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एनसीईआरटी एक्झांप्लर Physics Exemplar [English] Class 12
अध्याय 15 Communication Systems
Exercise | Q 15.18 | पृष्ठ १०२

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