Question

(A) What do you mean by barrier potential of diode?
(B) With help of a diagram explain the working of a full wave rectifier.

Answer 1

A) The potential barrier in the p-n junction diode is the barrier which does not allow charge flow across the junction normally. This barrier is created by the charge present in the space charge region. When p-type material is brought in contact to a n-type material, the charge flow across the junction takes place due to concentration gradient between the two sides (n and p type). But after some time the immobile ions are created near the contact which create electric field which opposes flow of current. This resistance to the flow of charge is known as barrier potential.
B) Full wave rectifier:
A full rectifier is an arrangement of four or more diodes in a bridge circuit configuration which provides the same output polarity for either input polarity. It is used for converting an alternating current (AC) input into a direct current (DC) output.
For half cycle of input AC, one diode out of the two, will get forward biased and will conduct, while the other diode, being reverse biased, will not conduct. For other cycle of input signal, the diode, which was reverse biased, will get forward biased and will conduct, and the other diode will get reverse biased and will stop conducting. Hence we obtain a unidirectional output voltage for the positive as well as for negative half cycles.