What happens in a forward-biased LED?
Answer and explanation
Correct answer: C. Electrons and holes recombine at the junction
- Step 1: In forward bias, electrons and holes move towards the junction.
- Step 2: When they recombine, energy is released as light.
Answer
Electrons and holes recombine at the junction.
Why not the others: Current flows only in the reverse direction: an LED conducts when forward-biased. The junction absorbs light to produce current: this describes a solar cell. The depletion layer widens: forward bias narrows it.
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