In a negative feedback amplifier the gain without feedback is 100, feedback ratio is
1/25 and input voltage is 50 mV. Calculate :
25
(i) gain with feedback (ii) feedback factor.
Answers
Gain with feedback and feedback factor are 20 and 5 respectively
To find : The gain with feedback and the gain factor
Given :
It is given that the gain without feedback is 100, feedback ratio is and input voltage is 50 mV.
Let us denote gain without feedback as A and gain with feedback as G. Feedback ratio is denoted by β.
Then,
Gain with feedback
Feedback factor,F is given by
∴Feed back factor
Feedback factor
Hence, (i)the gain without feedback is 20 and (ii) the feedback factor is 5
To learn more..
1. The voltage gain of an amplifier without feedback is
100. Find voltage gain with 7% of negative
feedback.
brainly.in/question/15064214
(i) The gain with feedback is 20
(ii) The feedback factor is 5
Explanation:
The gain with feedback is given by the formula:
Af = A/(1 + βA)
Where,
A = Gain without feedback = 100
β = Feedback ratio = 1/25
On substituting the values, we get,
Af = 100/(1 + (1/25 × 100))
Af = 100/(1 + 4)
Af = 100/5
∴ Af = 20
The feedback factor is given by the formula:
F = 1 + βA
On substituting the values, we get,
F = 1 + (1/25 × 100)
F = 1 + 4
∴ F = 5