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An amplitude modulated signal is plotted...

An amplitude modulated signal is plotted below:

Which one of the following best describles the above signal ?

A

`(9 + sin (2xx 10 ^(4) t )) sin (2.5 pi 10 ^(5) t ) V `

B

`(1+ 9 ( 2pi xx 10 ^(4) t )) sin ( 2.5 pi xx 10 ^(5)t ) V `

C

`(9 + sin ( 4 pi xx 10 ^(4)t ) ) sin (5 pi x x10 ^(5)t )V`

D

`( 9+ sin (2.5 pi 10 ^(5) t ) ) sin (2 pi xx 10 ^(4) t )V`

Text Solution

Verified by Experts

The correct Answer is:
A
`C _(m) (t) = (A_(c) + A_(m)sin omega _(m) t ) sin omega _(C)t`
`A _(C) + A_(m) = 10V`
` A _(C)-A_(m) =8V therefore A (C)=9 V`
`omega _(C) = (2pi)/(8xx 10 ^(-6)) =2.5 xx 10 ^(5) pi," " omega _(m) = (2pi)/(100xx10^(-6))=2xx 10 ^(4) pi.`
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