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Assertion : Light emitting diode (LED) e...

Assertion : Light emitting diode (LED) emits spontaneous radiation.
Reason : LED are forward biased p-n junctions.

A

If both assertion and reason are true and reason correct explanation of assertion.

B

If both assertion and reason are true but reason the correct explanation of assertion.

C

If assertion is true but reason is false.

D

If both assertion and reason are false.

Text Solution

Verified by Experts

The correct Answer is:
A
When a junction dipole is forward biased as shown in figure, energy is released at the junction due to recombination of electrons and hole. In the junction dipole made of gallium arsenide or indium phosphide, the energy is released in visible region. Such a junction dipole is called light emitting dipole or `LED`. the radiated enegry emitted by `LED` is equal or less than the band gap of semiconductor.
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