Concept:A \( \text{P-N} \) junction is forward-biased when an external potential lowers the built-in potential barrier, enabling majority charge carriers to cross the junction.
Formula:$$V_{\text{net}} = V_{\text{barrier}} - V_{\text{applied}}$$
Solution:- Connecting the positive terminal of an external DC source to the \( \text{P} \)-type material repels holes toward the junction.
- Connecting the negative terminal to the \( \text{N} \)-type material repels free electrons toward the junction.
- This reduces the depletion width and allows heavy forward conduction once \( V_{\text{applied}} > V_{\text{barrier}} \).
Why other options are incorrect:- Option A: Connecting \( \text{P} \) to negative and \( \text{N} \) to positive widens the depletion layer, establishing reverse bias.
- Option C: Connecting both terminals to the positive terminal results in zero potential difference across the junction.
- Option D: Connecting both terminals to the negative terminal creates an equipotential state with zero net current.
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