Question:
A LED emits visible light when its
A LED emits visible light when its
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An LED works in forward bias, where recombination of electrons and holes releases energy as photons.
Updated On: Nov 12, 2026
- junction is hot.
- holes and electrons recombine.
- depletion region widens.
- junction is reverse biased.
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The Correct Option is B
Solution and Explanation
Step 1: Understanding the Concept
A light emitting diode (LED) is a p-n junction diode that is forward biased.
Step 2: Working
In forward bias, electrons from the n-side and holes from the p-side cross the junction.
Near the junction they recombine.
Step 3: Light Emission
When an electron falls from the conduction band to the valence band, the released energy is emitted as a photon of visible light.
So the correct statement is option (B).
Final Answer:
An LED emits light when electrons and holes recombine at the junction. \[ \boxed{\text{(B) }\text{holes and electrons recombine}} \]
A light emitting diode (LED) is a p-n junction diode that is forward biased.
Step 2: Working
In forward bias, electrons from the n-side and holes from the p-side cross the junction.
Near the junction they recombine.
Step 3: Light Emission
When an electron falls from the conduction band to the valence band, the released energy is emitted as a photon of visible light.
So the correct statement is option (B).
Final Answer:
An LED emits light when electrons and holes recombine at the junction. \[ \boxed{\text{(B) }\text{holes and electrons recombine}} \]
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