Planck–Einstein Relation
Definition
E = hν = hc/λ, relating photon energy to frequency and wavelength. Wave descriptions account for interference, diffraction and polarisation, while photon energy helps describe quantised interactions. Energy per photon is not total exposure or biological harm.
- Context
- Electromagnetic radiation
For example, doubling frequency doubles energy per photon under E = hν, while total delivered energy also depends on photon number.
Ionisation requires an appropriate interaction and target; wavelength alone does not describe every radiation effect.
Related terms
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- Mid-Infrared (Mid-IR)
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- Photon
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- Photon Energy
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- Refractive Index
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