Question

In common emitter amplifier,the low resistance of the output circuit is $500$ times the resistance of the input circuit.If $\alpha =0.98$,then find the voltage gain and the power gain?

• A. 23500,1300500
• B. 24500,1200500
• C. 22505,1300500
• D. 23500,1200500

Answer 1

The correct option is B 24500,1200500

We have, $\beta =\frac{\alpha }{1-\alpha }=\frac{0.98}{1-0.98}$
$\beta =49$
Voltage gain = $\beta \times$ resistance gain
As given resistance gain = 500
So, voltage gain $=49\times 500=24500$
And, Power gain $={\beta }^2\times$ resistance gain
$=(49{)}^2\times 500$
$=2401\times 500=1200500$