# In an amplifier, negative feedback is introduced with feedback fraction $\beta =0.01$. If voltage given with out negative feed back. is $2500$ what is voltage gain with negative feed back.

$(a)\;99.2 \\ (b)\;96.15 \\ (c)\;45.2 \\ (d)\;60.2$

$A= 2500$
$B= 0.01$
Voltage given with negative feedback is
$A_f =\large\frac{A}{1+A \beta}$
$\qquad =\large\frac{2500}{1+2500 \times 0.01}$
$\qquad=\large\frac{2500}{26}$
$\qquad =96.15$
Hence b is the correct answer.
answered Jan 28, 2014 by