LIGHT

Light, or visible light, is electromagnetic radiation of a wavelength that is visible to the human eye (about 400–700 nm), or up to 380–750 nm. In the broader field of physics, light is sometimes used to refer to electromagnetic radiation of all wavelengths, whether visible or not.

Three primary properties of light are:

* Intensity
* Frequency or wavelength
* Polarization

Light can exhibit properties of both waves and particles (photons). This property is referred to as wave–particle duality. The study of light, known as optics, is an important research area in modern physics.

 
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