Concept:A half-wave rectifier uses a single PN junction diode that is forward-biased during one half of the AC cycle (conducting current) and reverse-biased during the alternate half (blocking current).
Formula:$$\text{Conduction Angle } \theta = \pi\text{ rad} = 180^\circ \implies \text{Conduction Period } T_{\text{cond}} = \frac{T}{2}$$
Solution:- During the positive half-cycle, the diode anode is positive relative to the cathode, forward-biasing the diode and allowing current to flow to the load.
- During the negative half-cycle, the diode becomes reverse-biased and behaves as an open circuit, blocking current flow.
- Thus, conduction occurs for exactly one-half (\( 50\% \)) of the input alternating cycle.
Why other options are incorrect:- Option A: Full-cycle conduction occurs only in linear resistive AC circuits or full-wave bridge rectifiers with alternating diode pairs, not a single diode half-wave rectifier.
- Option C: A diode conducts for \( 180^\circ \), not \( 270^\circ \) (three-quarters).
- Option D: A quarter-cycle conduction occurs only in specific peak-clipping or phase-controlled thyristor circuits.
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