Question

demonstrate an experiment to switch on and off led using transistor

Answer 1

The circuit above is called a low-side switch, because the switch – our transistor – is on the low (ground) side of the circuit. Alternatively, we can use a PNP transistor to create a high-side switch: Similar to the NPNcircuit, the base is our input, and the emitter is tied to a constant voltage.

Answer 2

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