Given: Threshold wavelength =660nm.
Therefore, energy required(or band gap energy) Eg=λhc=660×10−96.6×10−34×3×108J
=660×10−9×1.6×10−196.6×10−34×3×108eV
=815eV
So, X=15.
Conductivity of a photodiode starts changing only if the wavelength of incident light is less than 660nm. The band gap of photodiode is found to be (8X)eV. The value of X is:
(Given h=6.6×10−34Js,e=1.6×10−19C)
Held on 1 Feb 2024 · Verified 6 Jul 2026.
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