Q 12-14-022NEETJEE MainEasy
An LED is made from a semiconductor of band gap $2.48$ eV. The wavelength of the light it emits is about ($hc = 1240$ eV nm)
Answer: (B) $500$ nm
The emitted photon carries about the band gap energy:
$\lambda = \dfrac{hc}{E_g} = \dfrac{1240}{2.48} = 500$ nm (green light).
Solution by Sreeraj P, M.Sc Physics