which junction is forward biased when transistor is used as an amplifier?

For a transistor used as an amplifier (i.e., operating in the active region), the emitter–base junction is forward biased and the collector–base junction is reverse biased.

In the multiple-choice style often seen with this question, the correct statement is:

• Emitter–base junction forward biased,
• Collector–base (base–collector) junction reverse biased.

This biasing keeps the transistor in its active region, which is exactly where it works as a linear amplifier.

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