How does a transistor amplify an AC signal (when it works on DC and cannot change current direction)? - Quora
![Why is DC component ignored and AC analysis is used when obtaining input output impedance of a BJT transistor amplifier? - Electrical Engineering Stack Exchange Why is DC component ignored and AC analysis is used when obtaining input output impedance of a BJT transistor amplifier? - Electrical Engineering Stack Exchange](https://i.stack.imgur.com/lgo2U.gif)
Why is DC component ignored and AC analysis is used when obtaining input output impedance of a BJT transistor amplifier? - Electrical Engineering Stack Exchange
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