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A system has a gain of 80 db without feedback, if the negative feedback is 1/50th. What is the closed loop gain of the system in db with the addition of the negative feedback?

A system has a gain of 80 db without feedback, if the negative feedback is 1/50th. What is the closed loop gain of the system in db with the addition of the negative feedback? Correct Answer 34db

80db = 20log (G) Therefore, G= antilog 10(80/20) =10,000 Gv = G/ (1+GB) = 10,000/ (1+10,000/50) = 49.75 Gv (db) = 20log (49.75) = 34db.

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