Question

explain transistor as a switch

Answer 1

By turning a small input current into a large output current, the transistor acts like an amplifier. But it also acts like a switch at the same time. When there is no current to the base, little or no current flows between the collector and the emitter. Turn on the base current and a big current flows.

Answer 2

NPS transistor as a switch Based on the vlotage applied to the base terminal of transistor switching operating is performed when a sufficient voltage is applied between the base and emmiter collect the emmiter voltage is approximately equal to zero if there the transistor is short circuit