Q124 / 150 · MHT CET 2026 (15 April Shift 1) · Physics
If p-n junction diode is forward biased then
- Correct answerAwidth of depletion layer decreases.
- Bwidth of depletion layer increases.
- Cbarrier voltage increases
- Delectric conduction is not possible
Solution
When a p-n junction diode is forward biased, the positive terminal of the external voltage source is connected to the p-side and the negative terminal to the n-side.
The applied forward voltage opposes the built-in potential barrier, reducing the effective barrier voltage.
This external electric field pushes the majority charge carriers (holes in the p-region and electrons in the n-region) towards the junction.
As the carriers move towards the junction, they neutralize some of the immobile ions, which causes the width of the depletion layer to decrease.
This allows majority carriers to cross the junction easily, facilitating electric conduction.
Answer: width of depletion layer decreases.
The applied forward voltage opposes the built-in potential barrier, reducing the effective barrier voltage.
This external electric field pushes the majority charge carriers (holes in the p-region and electrons in the n-region) towards the junction.
As the carriers move towards the junction, they neutralize some of the immobile ions, which causes the width of the depletion layer to decrease.
This allows majority carriers to cross the junction easily, facilitating electric conduction.
Answer: width of depletion layer decreases.
Hence, the correct answer is option: 'A'.