JEE Mains · Physics · STD 12 - 12. atoms
For \(LED's\) to emit light in visible region of electromagnetic light, it should have energy band gap in the range of
- A \(0.1\, eV\) to \(0.4\,eV\)
- B \(0.5\, eV\) to \(0.8\,eV\)
- C \(0.9\, eV\) to \(1.6\,eV\)
- D \(1.7\, eV\) to \(3.0\,eV\)
Answer & Solution
Correct Answer
(D) \(1.7\, eV\) to \(3.0\,eV\)
Step-by-step Solution
Detailed explanation
Energy band gap range is given by, \(E_{g}=\frac{h c}{\lambda}\) For visible region \(\lambda=\left(4 \times 10^{-7}-7 \times 10^{-7}\right) \mathrm{m}\) \({{E_g} = \frac{{6.6 \times {{10}^{ - 34}} \times 3 \times {{10}^8}}}{{7 \times {{10}^{ - 7}}}}}\)…
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