Question

The circuit diagram of a full wave rectifier is shown

1. Explain how its works? Also draw the output wave form 

2. If the frequency of a.c. at the input is 50 Hz what will be the output frequency ?

Answer 1

Full wave rectifier consists of transformer two diodes and a load resistance R_L . Input a.c signal is applied across the primary of the transformer. Secondary of the transformer is connected to D₁ , and D₂ . The output is taken across R_L .

Working:

During the +ve half cycle of the a.c signal at secondary, the diode D₁ is forward biased and D₂ is reverse biased. So that current flows through D₁ and R_L .

During the negative half cycle of the a.c signal at secondary, the diode D₁ is reverse biased and D₂ is forward biased. So that current flows through D₂ and R_L .

Thus during both the half cycles, the current flows through R_L in the same direction. Thus we get a +ve voltage across R_L for +ve and -ve input. This process is called full wave rectification.

2. 100Hz