Q. In common emitter amplifier, the current gain is 62. The collector resistance and input resistance are 5 k$\Omega$ and 500 $\Omega$ respectively. If the input voltage is 0.01 V, the output voltage is
A) 0.62 V
B) 6.2 V
C) 62 V
D) 620 V
Explanation
(b) Voltage gain = resistance gain $\times$ current gain
Or $\frac{V_{out}}{V_{in}}$ =$\frac{R_{out}}{R_{in}}$ $\times \beta$
Or $V_{out} = \frac{R_{out}}{R_{in}}$ $\times \beta \times V_{in}$
$\therefore$ $V_{out} = \frac{5000}{500} \times 62 \times 0.01 = 6.2$ V
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.