Electronic Devices Question 21
Question: Consider an NPN transistor amplifier in common-emitter configuration. The current gain of the transistor is 100. If the collector current changes by 1 mA, what will be the change in emitter current
[AIIMS 2005]
Options:
A) 1.1 mA
B) 1.01 mA
C) 0.01 mA
D) 10 mA
Show Answer
Answer:
Correct Answer: B
Solution:
Current gain $ \beta =\frac{\Delta i _{c}}{\Delta i _{b}} $
$ \Rightarrow \Delta i _{b}=\frac{1\times {{10}^{-3}}}{100}={{10}^{-5}}A $ =0.01mA.
By using $ \Delta i _{e}=\Delta i _{b}+\Delta i _{c} $
$ \Rightarrow \Delta i _{e} $ = 1.01 + 1 = 1.01mA.
