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phosphorescence

(Encyclopedia)phosphorescence fŏsˌfərĕsˈəns [key], luminescence produced by certain substances after absorbing radiant energy or other types of energy. Phosphorescence is distinguished from fluorescence in th...

Kourou

(Encyclopedia)Kourou, town and commune (2007 pop. 25,918), N French Guiana, on the coast 26 mi (42 km) NW of Cayenne. A rocket-launching base, the Guiana Space Center, is mainly in the commune near the town; the So...

power, in physics

(Encyclopedia)power, in physics, time rate of doing work or of producing or expending energy. The unit of power based on the English units of measurement is the horsepower, devised for describing mechanical power b...

prime mover

(Encyclopedia)prime mover: see energy, sources of. ...

Cook, Thomas

(Encyclopedia)Cook, Thomas, 1808–92, English travel agent. In Leicester in 1841 he founded a travel agency under his name. The idea of the guided tour met with quick success, and by 1852 Cook had moved his office...

Federal Aviation Administration

(Encyclopedia)Federal Aviation Administration (FAA), component of the U.S. Department of Transportation that sets standards for the air-worthiness of all civilian aircraft, inspects and licenses them, and regulates...

Lenz's law

(Encyclopedia)Lenz's law, physical law, discovered by the German scientist H. F. E. Lenz in 1834, that states that the electromotive force (emf) induced in a conductor moving perpendicular to a magnetic field tends...

photoelectric effect

(Encyclopedia)photoelectric effect, emission of electrons by substances, especially metals, when light falls on their surfaces. The effect was discovered by H. R. Hertz in 1887. The failure of the classical theory ...

phosphorylation

(Encyclopedia)phosphorylation, chemical process in which a phosphate group is added to an organic molecule. In living cells phosphorylation is associated with respiration, which takes place in the cell's mitochondr...

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