Concept:A center-tapped full-wave rectifier requires a center-tapped secondary transformer winding and two diodes operating alternately on opposite half-cycles.
Formula:$$N_{\text{diodes}} = 2 \quad (\text{Center-tapped configuration})$$
Solution:- During the positive half-cycle, diode \( D_1 \) is forward-biased and conducts through the upper half-winding.
- During the negative half-cycle, diode \( D_2 \) is forward-biased and conducts through the lower half-winding.
- Thus, exactly two diodes provide full-wave rectification.
Why other options are incorrect:- Option A: A single diode produces half-wave rectification.
- Option C: Four diodes are required for a full-wave bridge rectifier, which does not require a center-tapped transformer.
- Option D: Three-diode configurations are non-standard and do not form a symmetrical single-phase rectifier.
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