photon
A quantum of electromagnetic radiation, usually considered as the elementary particle responsible for electromagnetic phenomena, including light.
Photons are unique in that they are massless, always travel at the speed of light in a vacuum, and are both a particle and a wave (exhibiting wave-particle duality).
Word relationships
- light quantum: An older, more descriptive term; 'photon' is the standard scientific name.
Commonly confused with
- electron: An electron is a charged matter particle with mass; a photon is a massless, chargeless force-carrying particle of light.
Word family
- photonic (adjective): relating to photons or light
Collocations
- light photon
- gamma-ray photon
- photon emission
- photon absorption
Example sentences
- "When light hits a solar panel, individual photons transfer their energy to electrons, generating an electric current." Describing the nature of light.
- "A photon is the force carrier for the electromagnetic force, mediating interactions between charged particles." Explaining quantum interactions.
- "The term 'photon' was coined by Gilbert N. Lewis in 1926, though the concept of light quanta had been introduced by Einstein and Planck earlier." A historical perspective.
Memory hook
Think of a 'PHOTO'graph, which is made by light. A 'photon' is the tiny particle of light that makes the photo possible. Light particle
When not to use
Use 'photon' specifically when referring to the quantum particle of light or electromagnetic radiation, not just 'light' in general.
Fun facts
- Photons are their own antiparticles.
- The energy of a photon is directly proportional to its frequency, a relationship described by Planck's constant.
Related words
Explore more words
electromagnetic, Quantum, radiation, photovoltaic, duality, charge
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