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Mean optical power launched into an 8 km...

Mean optical power launched into an `8 km` fibre is `120 muW` and mean output power is `4 muW`, then the overall attenuation is (Given log `30=1.477`)

A

`14.77` dB

B

`16.77` dB

C

`3.01` dB

D

None of these

Text Solution

Verified by Experts

The correct Answer is:
a
Attenuation `=10" log"(120)/(4)=10 log 30`
`=10xx1.4771=14.77 dB`.
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