A collection of atoms has 20% of the sample in a state 5.9 eV above the ground state. If these emit coherent radiation, what is the wavelength of the laser light produced? (c = 3.00 × 10⁸ m/s,
H = 6.626 × 10^-34 J ∙ s, 1 eV = 1.60 × 10^-19 J)

Question

Quizplus · Accepted Answer

The energy of a photon is given by E = hc/λ, where h is Planck's constant, c is the speed of light, and λ is the wavelength. The energy difference between the two states is 5.9 eV, which is equal to 9.44 × 10^-19 J. Therefore, the wavelength of the laser light produced is:λ = hc/E = (6.626 × 10^-34 J ∙ s)(3.00 × 10^8 m/s)/(9.44 × 10^-19 J) = 210 nm

A Collection of Atoms Has 20% of the Sample in a State