Concept:Once a silicon PN junction is forward-biased beyond its knee voltage, the forward voltage drop stabilizes around \( 0.7\text{ V} \) due to the steep exponential I-V curve.
Formula:$$V_F \approx V_k \approx 0.7\text{ V} \quad (\text{for Silicon})$$
Solution:- In forward conduction, the external supply overcomes the internal barrier potential.
- Because the forward I-V characteristic is very steep, the diode maintains a nearly constant forward voltage drop of \( \approx 0.6\text{ V} \) to \( 0.7\text{ V} \) across a wide range of operating currents.
Why other options are incorrect:- Option B: 0.0 V is an idealization that ignores the semiconductor material's bandgap.
- Option C: 5.0 V would cause excessive power dissipation and destroy a standard diode.
- Option D: The diode drops only its forward threshold voltage (\( \approx 0.7\text{ V} \)); the remaining voltage drops across the series load resistor.
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