Question

The collector supply voltage in CE transistor amplifier is $10V$. The base current is $10\mu A$ in the absence of the signal voltage and the voltage between the collector and the emitter is $4V$. The current gain $\left(\beta \right)$ of a transistor is $200$, then the value of the load resistance $R_L$

• A. $2k\Omega$
• B. $1k\Omega$
• C. $3k\Omega$
• D. $4k\Omega$

Answer 1

Answer: (C)

$3k\Omega$

Given, $\beta =200,\Delta I_B=10\mu A$
$=10\times {10}^{-6}A={10}^{-5}A$
$\beta =\left(\frac{\Delta I_C}{\Delta I_B}\right)$
$\Rightarrow \Delta I_C=\beta \Delta I_B$
$\Rightarrow \Delta I_C=200\times {10}^{-5}=2\times {10}^{-3}A$
and $R_L=\frac{\Delta V_{CE}}{\Delta I_C}=\frac{(10-4)}{2\times {10}^{-3}}=\frac{6}{2\times {10}^{-3}}$
$=3\times {10}^3\Omega =3k\Omega$