Question

For a transistor in common base, the current gain is $0.95$. If the load resistance is $400k\Omega$ and input resistance is $200\Omega$, then the voltage gain and power gain will be

• A. $1900$ and $1800$
• B. $1900$ and $1805$
• C. $5525$ and $3591$
• D. $1805$ and $1900$

Answer 1

The correct option is B $1900$ and $1805$

Given, $\alpha =0.95,R_0=400\times {10}^3\Omega$
$R_i=200\Omega$
As, voltage gain $=\alpha \frac{R_0}{R_i}=0.95\times \frac{400\times {10}^3}{200}=1900$
Power gain $=$ Voltage gain $\times$ Current gain
$1900\times 0.95=1805$.