Concept:In a bridge rectifier, the four diodes operate in diagonally opposite pairs. During any given half-cycle, one diagonal pair of diodes is forward-biased and conducts current in series through the load, while the other pair is reverse-biased and blocks current.
Formula:Qualitative concept / No formula required.
Solution:- Positive half-cycle: Diodes \(D_1\) and \(D_3\) conduct (total = 2 diodes).
- Negative half-cycle: Diodes \(D_2\) and \(D_4\) conduct (total = 2 diodes).
- Therefore, exactly 2 diodes conduct simultaneously during each half-cycle.
Why other options are incorrect:- Option A: Only 1 diode conducts at a time in a half-wave rectifier or center-tapped full-wave rectifier.
- Option C: A bridge rectifier never activates three diodes concurrently during normal operation.
- Option D: All 4 diodes conducting at once would cause a direct short-circuit of the AC source.
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