Question

An amplifier has a bandwidth of 500 kHz and a voltage gain of 100. If a negative feedback is introduced to extend the bandwidth to 5 MHz, then the value of new gain is ___

• A. 10

Answer 1

The correct option is A 10
New modified bandwidth is given by,

$B{W}_{new}=BW(1+A\beta )$

$5\times {10}^6=500\times {10}^5(1+\beta 100)$

$\beta =0.09$

New gain = $A_f=\frac{A}{1+A\beta }=\frac{100}{1+(100\times 0.09)}=10$