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)
A) 8.9 × 1019
B) 8.9 × 1018
C) 5.9 × 1019
D) 2.7 × 1018


Answer: A

Physics & Space Science

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