JEE Mains · Physics · STD 12 - 14. Semicondutor electronics
The energy band gap of semiconducting material to produce violet (wavelength \(=4000 \,A^{\circ}\) ) LED is \(.......eV\). (Round off to the nearest integer).
- A \(3\)
- B \(2\)
- C \(4\)
- D \(1\)
Answer & Solution
Correct Answer
(A) \(3\)
Step-by-step Solution
Detailed explanation
\(E _{ g }=\frac{ hc }{\lambda}=\frac{1242}{\lambda( nm )}=\frac{1242}{400}=3.105\) Answer rounded to \(3\,eV\)
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