Question

How does a diode act as a rectifier?

Answer 1

Hint: In a large number of electronic circuits in day-to-day appliances, we require DC voltage for operation. We can easily convert the alternating voltage or alternating current into direct voltage or direct current by using rectifiers created from diodes.

Complete answer:
A rectifier is a device that converts an Alternating Current (AC) into a Direct Current (DC) by using one or more contact diodes.
When the voltage is applied to the P-N junction diode, which is a semiconductor diode, in such a way that the positive terminal of the battery is connected to the p-type end of the PN junction diode and the negative terminal of the battery is connected to the n-type end, the diode is said to be forward-biased. In this state, the P-N junction diode allows current to flow in the circuit.
Similarly, when the voltage is applied to the P-N junction diode in such a way that the positive terminal of the battery is connected to the n-type end and the negative terminal of the battery is connected to the p-type end, the diode is said to be reverse biased. In this state, the diode does not allow the circuit to flow in the circuit. Thus, the diode allows current in forwarding bias conditions and blocks current in reverse bias condition. In simple words, a diode allows current in just one direction. This unique property of the diode allows it to act sort of a rectifier by converting an alternating current to a DC source.

Note:
There are two primary methods of diode rectification: Half Wave Rectifier and Full Wave Rectifier which differ in how efficiently they convert an AC source into a DC source. Half-wave rectifiers use diodes in one direction to allow current during one cycle of the AC flow but block it in the other while full-wave rectifiers use a combination of diodes in opposite directions to allow flow during both the cycles of the AC flow.