Concept:A center-tapped full-wave rectifier uses two diodes. Each diode conducts individually during alternating \( 180^\circ \) half-cycles.
Formula:$$\text{Conduction: } D_1 \text{ conducts during } [0, \pi], \quad D_2 \text{ conducts during } [\pi, 2\pi]$$
Solution:- Diode \( D_1 \) conducts during the positive half-cycle when the upper winding is positive relative to the center tap.
- Diode \( D_2 \) conducts during the negative half-cycle when the lower winding is positive relative to the center tap.
- Thus, two diodes alternate conduction, with one active during each half-cycle.
Why other options are incorrect:- Option A: A single conducting diode produces half-wave rectification.
- Option C: Four diodes conducting in pairs is the operating mode of a bridge rectifier.
- Option D: Three diodes do not form a standard single-phase rectifier topology.
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