How is a transistor biased to be in active state?

(a) Differentiate between three segments of a transistor on the basis of their size and level of doping. (b) How is a transistor biased to be in active state? (c) With the help of a necessary circuit diagram, describe briefly how n-p-n transistor in CE configuration amplifies a small sinusoidal input voltage. Write the expression for the ac current gain.

When is a transistor said to be in active state ?

Which one of the following circuits shows correct biasing of a PNP transistor to operate in active region in the CE mode-

Which one of the following circuits shows correct biasing of a PNP transistor to operate in active region in the CE mode-

When a transistor is operated in the active region, it cannot be used

How is the emitter base junction in the transistor biasing ?