COMEDK · Physics · 27. Dual Nature of Matter
What is the maximum wave length of EM radiation required to move an electron from the valance band to conduction band of a semiconductor? [Given :Energy gap \(\mathrm{E}_{\mathrm{g}}=1.98 \times 10^{-19} \mathrm{~J}\); Planck's constant \(h=6.6 \times 10^{-34} \mathrm{Js}\) ]
- A \(10^{-6} \mathrm{~m}\)
- B \(10^{-9} \mathrm{~m}\)
- C \(10^{-10} \mathrm{~m}\)
- D \(10^{-12} \mathrm{~m}\)
Answer & Solution
Correct Answer
(A) \(10^{-6} \mathrm{~m}\)
Step-by-step Solution
Detailed explanation
The energy required to move an electron from the valence band to the conduction band is given by the energy gap \(E_{g}\). The relationship between the energy of a photon and its wavelength \(\lambda\) is given by \(E = \dfrac{hc}{\lambda}\). To find the maximum wavelength…
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