Suppose the energy liberated in the recombination of a hole-electron pair is converted into electromagnatic radiation. If the maximum wavelength emitted is 660nm, what is the band width? (Use `h=6.6xx10^(-34) J-s)`

Options

A. 0.1875 eV
B. 1.875 eV
C. 0.938 eV
D. 0.625 eV

Answer

B

Explanation

Here `lambda=660 nm=660xx10^(-9)m`
Band gap `E_(g)=(hc)/(lambda)=((6.6xx10^(-34))xx(3xx10^(8)))/(660xx10^(-9))`
`(6.6xx10^(-34)xx3xx10^(8))/(660xx10^(-9)xx1.6xx10^(-19))ev`
`=1.875 eV`