JEE Mains · Physics · STD 12 - Semicondutor electronics
- JEE Mains 2024
- Hard
- MCQ
Conductivity of a photodiode starts changing only if the wavelength of incident light is less than \(660 \mathrm{~nm}\). The band gap of photodiode is found to be \(\left(\frac{x}{8}\right) \mathrm{eV}\). The value of \(x\) is _______. (Given, \(\mathrm{h}=6.6 \times 10^{-34} \mathrm{Js}, \mathrm{e}=1.6 \times 10^{-19} \mathrm{C}\) )
Pick an option to check your answer.
Answer & Solution
Correct Answer
(A) \(15\)
Step-by-step Solution
Detailed explanation
\(\mathrm{E}_{\mathrm{s}}=\frac{\mathrm{hc}}{\lambda}=\frac{6.6 \times 10^{-34} \times 3 \times 10^8}{660 \times 10^{-9}} \mathrm{~J}\)
\(=\frac{6.6 \times 10^{-34} \times 3 \times 10^8}{660 \times 10^{-9} \times 1.6 \times 10^{-19}} \mathrm{eV}\)
\(=\frac{15}{8} \mathrm{eV}\)
So \(x=15\)
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