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planetesimal theory

(Encyclopedia)planetesimal theory plănˌĭtĕsˈəməl [key]: see solar system. ...

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...

civil time

(Encyclopedia)civil time, local time based on universal time. Civil time may be formally defined as mean solar time plus 12 hr; the civil day begins at midnight, while the mean solar day begins at noon. Civil time ...

Nuclear Regulatory Commission

(Encyclopedia)Nuclear Regulatory Commission (NRC), an independent U.S. government commission, created by the Energy Reorganization Act of 1974 and charged with licensing and regulating civilian use of nuclear energ...

heating

(Encyclopedia)CE5 Typical warm-air heating system heating, means of making a building comfortably warm relative to a colder outside temperature. Old, primitive methods of heating a building or a room within it ...

McMahon, Brien

(Encyclopedia)McMahon, Brien (James O'Brien McMahon), 1903–52, American statesman, b. Norwalk, Conn. After practicing law, he became a judge in Norwalk, and from 1933 to 1936 he served in the office of the U.S. A...

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...

exoplanet

(Encyclopedia)exoplanet or extrasolar planet, a planet located outside the solar system. See planet; planetary system. ...

prime mover

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

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...