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light

(Encyclopedia)light, visible electromagnetic radiation. Of the entire electromagnetic spectrum, the human eye is sensitive to only a tiny part, the part that is called light. The wavelengths of visible light range ...

light bulb

(Encyclopedia)light bulb: see lighting.

light horse

(Encyclopedia)light horse, any breed of horse that is used primarily for riding or for light work such as pulling buggies. Light horses have their origin in the Middle East and N Africa. All modern breeds of light ...

light-year

(Encyclopedia)light-year, in astronomy, unit of length equal to the distance light travels in one sidereal year. It is 9.461 × 1012 km (about 6 million million mi). Alpha Centauri and Proxima Centauri, the stars n...

Drummond light

(Encyclopedia)Drummond light: see calcium oxide. ...

black light

(Encyclopedia)black light: see ultraviolet radiation. ...

zodiacal light

(Encyclopedia)zodiacal light or zodiacal band, a faint band of light sometimes seen in the western sky just after sunset in the spring, extending up from the horizon at the point where the sun has just set, or in t...

light-emitting diode

(Encyclopedia)light-emitting diode: see diode.

electric-light bug

(Encyclopedia)electric-light bug: see water bug. ...

polarization of light

(Encyclopedia)polarization of light, orientation of the vibration pattern of light waves in a singular plane. Unpolarized light can be converted into a single polarized beam by means of the Nicol prism, a device ...