Concept:A bridge rectifier uses four diodes arranged in a bridge loop. Diode pairs conduct on alternate half-cycles to maintain unidirectional current through the load.
Formula:$$V_{\text{load, peak}} = V_m - 2 V_{\text{barrier}}$$
Solution:- During the positive half-cycle, two diagonally opposite diodes (e.g., \( D_1 \) and \( D_3 \)) are forward-biased and conduct in series with the load.
- During the negative half-cycle, the other two diodes (\( D_2 \) and \( D_4 \)) are forward-biased and conduct in series with the load.
- At any point during conduction, exactly two diodes are active simultaneously.
Why other options are incorrect:- Option A: If all four diodes conducted simultaneously, the secondary winding would be short-circuited.
- Option B: Single-diode conduction occurs in half-wave and center-tapped full-wave rectifiers, not bridge rectifiers.
- Option D: Rectifiers operate symmetrically with balanced pairs of diodes; three-diode conduction does not occur.
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