AP EAMCET · PHYSICS · Semiconductors
For an \(L E D\) to emit light in visible region of the electromagnetic spectrum, it can have energy band gap in the range of, (Plank's constant, \(h=6.6 \times 10^{-34} \mathrm{Js}\) and speed of light, \(e=3 \times 10^8 \mathrm{~ms}^{-1}\) in vacuum)
- A 0.1 eV to 0.4 eV
- B 0.9 eV to 1.6 eV
- C 1.7 eV to 3.1 eV
- D 0.5 eV to 0.8 eV
Answer & Solution
Correct Answer
(C) 1.7 eV to 3.1 eV
Step-by-step Solution
Detailed explanation
Key Idea Frequency of visible rays range from \(4 \times 10^{14} \mathrm{~Hz}\) to \(7 \times 10^{14} \mathrm{~Hz}\). Maximum and minimum energy of photon in visible light,…
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