The voltage gain of an amplifier with `9%` negative feedback is `10`. The voltage gain without feedback will be

Options

A. 1.25
B. 100
C. 90
D. 10

Answer

B

Explanation

`"Voltage gain"=(A_(V))/(1+beta.A_(V)),`
where `beta=(9)/(100)=0.09`, voltage gain = 10
`rArr" "10=(A_(V))/(1+(9)/(100).A_(V))`
`rArr A_(V)=(10)/(0.1)=100`