Lasers: You need 14 W of infrared laser light power with wavelength 1270 nm to bore a hole in a diamond. How many downward atomic transitions per second must occur in the laser if all of them result in light directed onto the diamond? (c = 3.00 × 10⁸ m/s, h = 6.626 × 10^-34 J ∙ s)

Question

Quizplus · Accepted Answer

The energy of one photon is calculated using E = hc/λ. Substituting the given values, E = (6.626 × 10^-34 J∙s)(3.00 × 10^8 m/s) / (1270 × 10^-9 m) = 1.57 × 10^-19 J. The number of photons per second (transitions per second) is the power divided by the energy per photon: 14 W / 1.57 × 10^-19 J = 8.9 × 10^19 transitions per second.

Lasers: You Need 14 W of Infrared Laser Light Power