The majority charge carriers in an NPN transistors are-

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RSMSSB JE Electrical (Diploma) 19 May 2022 Official Paper

Answer 1

Majority Charge Carriers in NPN Transistors:

An NPN transistor is a type of bipolar junction transistor (BJT) where the majority charge carriers are electrons.
In an NPN transistor, the structure consists of a layer of P-type semiconductor sandwiched between two N-type semiconductors.
The N-type regions, which are the emitter and collector, have an abundance of electrons as they are doped with pentavalent (five-valence electron) elements like phosphorus.
In the P-type region, which is the base, there is a deficiency of electrons (holes), but this region is very thin compared to the N-type regions.
When the transistor is forward-biased, electrons are injected from the N-type emitter into the P-type base. These electrons are the majority carriers in the emitter and also in the collector.
The base is thin and lightly doped, so most of the electrons pass through the base and reach the collector, making electrons the majority charge carriers in the entire transistor.
As the electrons move from the emitter to the collector, a current is established, which is controlled by the base-emitter voltage.

Conclusion:

The majority charge carriers in an NPN transistor are electrons, which flow from the emitter to the collector through the base region.