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

detailed solution

Correct option is D

The process of injecting a fraction of output energy of some device back to the input is known  as feedback.  When the feedback energy (voltage or current) is out of phase with the input signal and thus opposes it,  then it is called negative feedback. Voltage gain with feedback is Avf=Av1+βAvwhere Avis voltage gain without feedback and β is negative feedback. Given Avf=10, β=9%=9100 10=Av1+9100Av              or   10+910Av=Av or     0.1 Av =10      or  Av = 100