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Question
For an amplitude modulated wave, the maximum amplitude is found to be 10 V while the minimum amplitude is found to be 2 V. Determine the modulation index μ. What would be the value of μ if the minimum amplitude is zero volt?
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Solution
Maximum amplitude, Amax = 10 V
Minimum amplitude, Amin = 2 V
Modulation index μ, is given by the relation:
`mu= (A_"max" - A_"min")/(A_"max" + A_"min")`
`= (10 - 2)/(10 + 2) = 8/12 = 0.67`
if A_"min" = 0
Then `mu = A_"max"/A_"max"= 10/10 = 1`
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