LED Operation and Bias – Rankers Physics

P-N Junction Diode and its applications: Practice Problem & Solution

Assertion (A): Light emitting diode (LED) emits self radiation. Reason (R): LED are reverse biased p-n junctions.  
Both (A) & (R) are true and the (R) is the correct explanation of the (A)
Both (A) & (R) are true but the (R) is not the correct explanation of the (A)
(A) is true but (R) is false
Both (A) and (R) are false

Short Solution (Best for NEET):

To solve this problem, we apply the core principles of P-N Junction Diode and its applications. Understanding the underlying formula is key to arriving at the correct answer below:

Concept: LED operation.
LEDs are \(p-n\) junctions that emit light when forward biased due to electron-hole recombination. Reverse biasing does not cause light emission. Thus, Assertion (A) is true, but Reason (R) is false.

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