Electronic Devices Question 223
Question: Assertion : In a common emitter transistor amplifier the input current is much less than the output current. Reason : The common emitter transistor amplifier has very high input impedance.
[AIIMS 2005]
Options:
A) If both assertion and reason are true and the reason is the correct explanation of the assertion.
B) If both assertion and reason are true but reason is not the correct explanation of the assertion.
C) If assertion is true but reason is false.
D) If the assertion and reason both are false.
E) If assertion is false but reason is true.
Show Answer
Answer:
Correct Answer: C
Solution:
In common emitter transistor amplifier current gain $ \beta >1, $ so output current > Input current, hence assertion is correct.
Also, input circuit has low resistance due to forward biasing to emitter base junction, hence reason is false.
