Concept:In forward bias, the externally applied electric field opposes the built-in electric field of the depletion layer, reducing the net potential barrier.
Formula:$$V_{\text{net}} = V_B - V_{\text{applied}}$$
Solution:- The positive terminal connected to the P-side repels holes toward the junction, and the negative terminal connected to the N-side repels electrons toward the junction.
- This reduces the net space charge, shrinking the width of the depletion layer and lowering the effective barrier potential.
Why other options are incorrect:- Option A: This describes the behavior under reverse bias conditions.
- Option B: Depletion width always correlates directly with the effective barrier height; it narrows as barrier potential decreases.
- Option C: The width is dynamically reduced as external bias increases.
Quality & Fidelity Assurance:
Every question on BeambePrep is rigorously curated against the official PMDC syllabus with zero filler, zero out-of-syllabus content, and zero typos. When an authentic past paper originally contained a historical mistake or ambiguity from the examining board (such as UHS or NUMS), BeambePrep faithfully reflects the original paper while detailing the nuance and scientific consensus in the autopsy above.