A 2 mW laser operates at a wavelength of 500 nm. The number of photons that will be emitted per second is:[Given Planck’s constant h = 6.6 × 10-34 Js, speed of light c = 3.0 × 108 6m/s]

A 2 mW laser operates at a wavelength of 500 nm. The number of photons

1.	A 2 mW laser operates at a wavelength of 500 nm. The number of photons that will be emitted per second is:[Given Planck’s constant h = 6.6 × 10-34 Js, speed of light c = 3.0 × 108 6m/s]
A.	5 × 1015
B.	1.5 × 1016
C.	2 × 1016
D.	1 × 1016
Answer» B. 1.5 × 1016

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A 2 mW laser operates at a wavelength of 500 nm. The number of photons that will be emitted per second is:[Given Planck’s constant h = 6.6 × 10-34 Js, speed of light c = 3.0 × 108 6m/s]

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