Question

The wavelength of a photon is 3000 A. The energy of the photon is ___________

(a) 3.47 eV

(b) 4.54 eV

(c) 6.78 eV

(d) 2.12 eV

I had been asked this question during an internship interview.

This interesting question is from Mechanism of Light Emission topic in chapter Optics of Engineering Physics II

Answer 1

The correct choice is (a) 3.47 eV

The explanation is: We know, E = hc/λ

= 6.6 X 10^-34 X 3 X 10^8/3 X 10^-7

= 6.6 X 10^-19

= 3.47 eV.