Draw the circuit diagram of a single phase full wave bridge rectifier and describe its operation and input and output voltage waveforms

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It contains 4 diodes d1 ,d2, d3, and d4 connected to form a bridge. The A.c supply to be rectified is applied to the opposite ends of the bridge through the transformer. And between the ends of the bridge the load resistance RL is connected. 

During the positive half-cycle of secondary voltage, the end P of the secondary winding becomes positive and end Q negative. This makes the diodes D1 and D3 to be forward biased while diodes D2 and D4 to be reverse biased. These two diodes will be in series through the RL hence current flows from point A to B through the load RL.

During the negative half-cycle of secondary voltage the end P becomes negative and end Q positive. This makes diodes D2 and D4 forward biased whereas diodes D1 and D3  are reverse biased. Therefore, only diodes D2 and D4 conducts. These two diodes will be in series through the load RL.

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