Q. A transistor is operated in common emitter configuration at VC = 2 V such that a change in the base current from 100 µA to 300 µA produces a change in the collector current from 10 mA to 20 mA. The current gain is
A) 25
B) 50
C) 75
D) 100
Explanation
[Solution from source] Common-emitter current gain β = ΔI_C/ΔI_B = (20 − 10) mA/(300 − 100) μA = 10 mA/0.2 mA = 50. Using the final values I_C/I_B = 20 mA/300 μA ≈ 67 or initial values 100 is the trap. Answer (2).
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.