Q. 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 connector 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
Explanation
(b) The collector current is given by
$I_{C} = \frac{V_{C}}{R_{C}} = \frac{0.6V}{600\Omega} = 1 \times 10^{- 3}A = 1mA$
$\beta = \frac{I_{C}}{I_{B}} \Rightarrow I_{B} = \frac{I_{C}}{\beta} = \frac{1mA}{20} = 0.05mA$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.