The Energy of Light Video Lessons

Concept: The Energy of Light

# Problem: Calculate the energy of a photon in joules if the wavelength is 5.48 x 10 2 nm.

###### FREE Expert Solution

We’re being asked how many photons per second are being emitted by a red laser with a wavelength of 5.48 x 10 2 nm.

Recall that the energy of a photon (E) is given by:

where:

h = Planck’s constant (6.626 × 10–34 J • s)

v = frequency (in s–1)

Also, recall that the frequency (v) and wavelength (λ) are related:

where:

c = speed of light (3.0 × 108 m/s)

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###### Problem Details

Calculate the energy of a photon in joules if the wavelength is 5.48 x 10 2 nm.