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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...

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...

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...

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...

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...

hydrophone

(Encyclopedia)hydrophone hīˈdrəfōnˌ [key], device that receives underwater sound waves and converts them to electrical energy; the voltage generated can then be read on a meter or played through a loudspeaker....

foot-pound

(Encyclopedia)foot-pound, abbr. ft-lb, unit of work or energy in the customary English gravitational system; it is the work done or energy expended by a force of 1 pound acting through a distance of 1 foot. It is e...