Q. In a common base amplifier circuit, calculate the change in base current if that in the emitter current is 2 mA and $\alpha = 0.98$
A) 0.04 mA
B) 1.96 mA
C) 0.98 mA
D) 2 mA
Explanation
(a) $\alpha = \frac{\mathrm{\Delta}I_{c}}{\mathrm{\Delta}I_{e}}\ \Rightarrow \ \mathrm{\Delta}I_{c} = 0.98 \times 2 = 1.96$ mA
$\mathrm{\Delta}I_{b} = \mathrm{\Delta}I_{e} - \mathrm{\Delta}I_{c} = 2 - 1.96 = 0.04$ mA.
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.