Question

A laser pulse with a wavelength of 525 nm

nm contains 4.40 mJ

mJ of energy. How many photons are in the laser pulse?

Accepted Answer

The laser pulse in this question has a wavelength of

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. To solve this problem, we first have to calculate the energy of a
single photon in the laser pulse. The equation for calculating the
energy of a single photon of an electromagnetic wave is where
 [/image?k=85bd0c4c3576ba41a3c9318cd390b501]
is the speed of light, is planks constant and is the wave length of
the photons.

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[/image?k=dc67ebaa19907fec1ca1b0f5edfc2901]

[/image?k=13cd8e4473c13738e24d69917d5801f1]

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= 1.16 × 1016 photons

Question #237183

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