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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? - Physics

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Question

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?

Short/Brief Note
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Solution

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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Chapter 15: Communication Systems - Exercise [Page 102]

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NCERT Exemplar Physics [English] Class 12
Chapter 15 Communication Systems
Exercise | Q 15.18 | Page 102

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