Q. The current gain of a transistor in the common base mode is 0.9. If the change in the emitter current is 5 mA, the change in the collector current will be
A) 4 mA
B) 4.5 mA
C) 5.6 mA
D) Zero
Explanation
(b) Current gain = $\frac{small\ change\ in\ collector\ current\ \left( {\mathrm{\Delta}i}_{c} \right)}{small\ change\ in\ emitter\ current\ \left( {\mathrm{\Delta}i}_{c} \right)}$
0.9 = $\frac{{\mathrm{\Delta}i}_{c}}{5}$
$\Rightarrow {\mathrm{\Delta}i}_{c}$= 0.9 $\times$ 5 = 4.5 mA
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.