Concept:A full-wave bridge rectifier uses four diodes in a bridge arrangement. Diagonal pairs alternate conduction on opposite half-cycles to direct load current in the same direction.
Formula:$$\text{Positive Half-Cycle: } D_1, D_3 \text{ (Forward Biased, ON)} \quad \text{and} \quad D_2, D_4 \text{ (Reverse Biased, OFF)}$$
Solution:- During the positive half-cycle, the top secondary terminal is positive relative to the bottom terminal.
- This forward-biases diagonal diodes \( D_1 \) and \( D_3 \), routing current through the load from top to bottom.
- Diodes \( D_2 \) and \( D_4 \) are reverse-biased and act as open switches.
Why other options are incorrect:- Option A: Simultaneous conduction of all four diodes would short-circuit the transformer secondary.
- Option B: Diodes \( D_2 \) and \( D_4 \) conduct during the negative half-cycle.
- Option C: Adjacent diodes \( D_1 \) and \( D_2 \) do not conduct simultaneously during standard rectification.
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