What is β (Beta) of a Transistor?

β (beta) of a transistor is the gain or amplification factor of a transistor. It is the factor by which current is amplified in the circuit.

So if a transistor has a β of 100, the base current that goes into it is amplified by 100. So, if the base current, Ib, going into a transistor is 30μA, the emitter current will be

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