Official Correct Choice:
Option C: From diode \( D_2 \), through the load resistor to the center tap, and through the lower half-winding
Concept:The center tap serves as the common return path for current delivered by either diode during its respective conducting half-cycle.
Formula:$$i_L(t) = i_{D2}(t) \quad (\text{during negative half-cycle})$$
Solution:- During the negative half-cycle, the bottom secondary terminal becomes positive with respect to the center tap.
- Diode \( D_2 \) conducts, directing current through the load resistor toward the center tap.
- The current returns to the bottom terminal through the lower half-winding, completing the circuit.
Why other options are incorrect:- Option A: Diode \( D_1 \) is reverse-biased during the negative half-cycle and does not conduct.
- Option B: The diodes conduct on alternate half-cycles, not in parallel.
- Option D: Current flows through the load resistor to deliver DC power.
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