Light is electromagnetic radiation, particularly radiation of a wavelength that is visible to the human eye (about 400–700 nm, or perhaps 380–750 nm). In physics, the term light sometimes refers to electromagnetic radiation of any wavelength, whether visible or not.
Four primary properties of light are:
Light, which exists in tiny "packets" called photons, exhibits properties of both waves and particles. This property is referred to as the wave–p...
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Light is electromagnetic radiation, particularly radiation of a wavelength that is visible to the human eye (about 400–700 nm, or perhaps 380–750 nm). In physics, the term light sometimes refers to electromagnetic radiation of any wavelength, whether visible or not.
Four primary properties of light are:
Light, which exists in tiny "packets" called photons, exhibits properties of both waves and particles. This property is referred to as the wave–particle duality. The study of light, known as optics, is an important research area in modern physics.
The speed of light in a vacuum is presently defined to be exactly 299,792,458 m/s (about 186,282 miles per second). This definition of the speed of light means that the metre is now defined in terms of the speed of light. Light always travels at a constant speed, even between particles of a substance through which it is shining. Photons excite the adjoining particles that in turn transfer the energy to the neighbor. This may appear to slow...
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