Structure of NPN Transistor

The NPN transistor is made up of collector, base and emitter. When the NPN transistor is connected to a proper voltage, the emitter will be supplied with electrons which are negatively charged.

The base which will receive the electrons from the emitter must be more positively charged than the emitter and the collector must also be more positively charged than the base.

NB: Like poles repel and unlike poles attract. The electrons will move from the emitter to the base due to the positivity levels of the base. The electrons will move from the base to the collector due to its high positivity level. The collector collects the electrons from the base