Question

The collector supply voltage is $6 \,V$ and the voltage drop across a resistor of $600\,\Omega$ . in the collector circuit is $0.6 \,V$, in a transistor connected in common emitter mode. If the current gain is $20$, the base current is

• A. $0.25\,mA$
• B. $0.05\,mA$
• C. $0.12\,mA$
• D. $0.02\,mA$

Answer 1

Answer: (B)

$0.05\,mA$

Answer 2

${{i}_{C}}{{R}_{C}}={{V}_{C}}$
${{i}_{C}}=\frac{{{V}_{C}}}{{{R}_{C}}}=\frac{0.6}{600}=1\,mA$
$\therefore$ $\beta =\frac{{{i}_{C}}}{{{i}_{B}}}$
or ${{i}_{B}}=\frac{{{i}_{C}}}{\beta }=\frac{1}{20}=0.05\,mA$