Light wiki:
>For other uses, see Light (disambiguation). Light is electromagnetic radiation with a wavelength that is visible to the eye (visible light) or, in a technical or scientific setting, electromagnetic radiation of any wavelength. The three basic dimensions of light (i.e., all electromagnetic radiation) are:intensity (or brilliance or amplitude), which is related to the human perception of brightness of the light,frequency (or wavelength), perceived by humans as the color of the light, andpolarization (or angle of vibration), which is not perceptible by humans under ordinary circumstances. Due to wave-particle duality, light simultaneously exhibits properties of both waves and particles. The precise nature of light is one of the key questions of modern physics.
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Bar wiki:
ay mean:A pole or stick, often made of wood or metal, sometimes used to mark a height, such as in high jump, or as a handrail, such as in ballet (where the word is usually spelled "barre") or Dance Dance Revolution, or as an obstacle.A quantity of a substance supplied as a bar-shaped piece: a bar of soap; a candy bar.A shape in which metal is traded, usually prior to further working: bar stockA law or rule preventing something.Bar (establishment), a retail establishment which serves alcoholic beverages (in Britain, a pub; in continental Europe, a café; in Italy, the term Bar is largely used, and is generally equivalent to caffé); Bar (counter), the counter from which drinks are dispensed in a Bar (establishment).Bar (unit), a scientific unit of pressure, roughly the atmosphere pressure on Earth at sea level. A millibar is 0.001 bar.Bar (music), a period of music.Bar association, the community of persons engaged in the practice of law.Bar (landform), a type of beach behind which lies a lagoon.Bar (diacritic), a line through a letter used as a diacritic.Toolbar, a visual menu with various icons.A macron over a digit or digits in mathematics used to indicated a repeating decimal.The second metasyntactic variable, after foo.Bar (Aramaic), a common prefix in New Testament Aramaic names, meaning son of and often indicating that the person is also known by another name.Bar (heraldry), a fess-like charge sometimes stated to be a diminutive of the fess.
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