An LED is constructed from a p-n junction diode using GaAsP. The energy gap is 1.9 eV. The wavelength of the light emitted will be equal to [NEET 2019]

Question

Accepted Answer

Correct answer: B. (b) The energy of light of wavelength is given by E= hv= hc ⇒ = hcE …….(i) Here, h= Planck's constant =6.63 10^-34 J-s c= speed of light=3 10^8 ms E= energy gap=1.9 eV =1.9 1.6 10^-19 J Substituting the given values in Eq. (i), we get ⇒ = 6.63 10^-34 3 10^81.9 1.6 10^-19 =6.54 10^-7 m ≈654 nm Thus, the wavelength of light emitted from LED will be 654 nm.

$An LED is constructed from a p - n junction diode using GaAsP. The energy gap is 1.9 eV. The wavelength of the light emitted will be equal to [NEET 2019]$

Solution

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