lightquantum
nounUK /ˈlaɪt ˈkwɒntəm/
US /ˈlaɪt ˈkwɑːntəm/
A light quantum is a tiny packet of light energy.
When the lamp shines, it sends out many light quanta.
OTHER MEANINGS
2. A single unit of electromagnetic energy that behaves like a particle.
Scientists measured the energy of each light quantum in the beam.
3. A quantum of radiant energy emitted or absorbed by an atom.
The atom released a light quantum as its electron dropped to a lower level.
4. In simple terms, a photon of visible or invisible light.
A light quantum can travel through space without needing a medium.