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Bode's law

(Encyclopedia)Bode's law [for J. E. Bode], also known as Titius's law or the Titius-Bode law, empirical relationship between the mean distances of the planets from the sun. If each number in the series 0, 3, 6, 12,...

diode

(Encyclopedia)diode dīˈōd [key], two-terminal electronic device that permits current flow predominantly in only one direction. Most diodes are semiconductor devices; diode electron tubes are now used only for a ...

ozone layer

(Encyclopedia)ozone layer or ozonosphere, region of the stratosphere containing relatively high concentrations of ozone, located at altitudes of 12–30 mi (19–48 km) above the earth's surface. Ozone in the ozone...

binary star

(Encyclopedia)CE5 A. Eclipsing binary: Primary component passing behind secondary (dimmer) component B. Light curve for eclipsing binary binary star or binary system, pair of stars that are held together by the...

perpetual-motion machine

(Encyclopedia)perpetual-motion machine, device that would be able to operate continuously and supply useful work, in violation of the laws of thermodynamics. A machine that would produce more energy in the form of ...

work

(Encyclopedia)work, in physics and mechanics, transfer of energy by a force acting to displace a body. Work is equal to the product of the force and the distance through which it produces movement. Although both fo...

automobile industry

(Encyclopedia)automobile industry, the business of producing and selling self-powered vehicles, including passenger cars, trucks, farm equipment, and other commercial vehicles. By allowing consumers to commute long...

Cockcroft, Sir John Douglas

(Encyclopedia)Cockcroft, Sir John Douglas, 1897–1967, English physicist, educated at the Univ. of Manchester and St. John's College, Cambridge. He was a fellow of St. John's College (1928–46) and professor of n...

voltaic cell

(Encyclopedia)voltaic cell, a simple device with which chemical energy is converted into electrical energy. Two dissimilar metals (e.g., copper and zinc) are immersed in an electrolyte (e.g., a dissolved sulfate). ...

Baruch, Bernard Mannes

(Encyclopedia)Baruch, Bernard Mannes bəro͞okˈ [key], 1870–1965, U.S. financier and government adviser, b. Camden, S.C. He grew rich through stockmarket speculation before he was 30. In World War I he advised o...