Photon Wavelength from Energy

The Photon Wavelength from Energy calculator compute the wavelength ( λ) of a photon based on Planck's constant (h), the speed of light (c) and the energy of the photon ( E).

INSTRUCTIONS: Choose units and enter the following:

• ( E) This is the energy of the photon

Wavelength of Photon (λ): The calculator returns the wavelength in meters.  However, this can be automatically converted to compatible units via the pull-down menu.

The Math / Science

The energy of a photon depends only on its wavelength.  The formula for the wavelength of a photon is:

          λ= h•c / E

where:

• λ= wavelength of the photon
• E = energy of the photon
• h = Planck's constant 
• c = speed of light ( 2.998 × 10⁸ m/s)

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