Explain, why the input resistance of a transistor is low and output re – InterviewSolution

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1.	Explain, why the input resistance of a transistor is low and output resistance is high.
Answer» While using a transister, the emitter-base junction is always forward biased and collectorbase junction is always reverse-biased. Due to it, a small change in emitter current. This means that a small signal voltage variation at the input of the transistor produces a large emitter current variation. This shown that the input resistance of a transistor is low. Since collector is reverse-biased, it collects all the charge carriers which diffuse into it, through base. Due to it a very large change in collector voltage shows only a small change in the collector current. This shows that the output resistance of the transistor is high.

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