Concept:During the negative half-cycle, the polarity of the secondary transformer terminals reverses with respect to the grounded center tap.
Formula:$$V_{\text{top}} = -V_m \sin(\omega t), \quad V_{\text{bottom}} = +V_m \sin(\omega t)$$
Solution:- The bottom terminal becomes positive relative to the center tap, forward-biasing diode \( D_2 \).
- The top terminal becomes negative relative to the center tap, reverse-biasing diode \( D_1 \).
- Current flows through \( D_2 \) and passes through the load resistor in the same direction as during the positive half-cycle.
Why other options are incorrect:- Option A: The diodes conduct alternately on opposite half-cycles rather than in parallel.
- Option B: Diode \( D_1 \) is reverse-biased by the negative potential at the top terminal.
- Option C: Zero load output during the negative half-cycle occurs in a half-wave rectifier, not a full-wave rectifier.
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