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fusion

(Encyclopedia)fusion, in physics. 1 The change of a substance from the solid to the liquid state, also known as melting. The heat given up by a unit mass of a substance during fusion is called the latent heat of fu...

Voronezh

(Encyclopedia)Voronezh Rus. vərôˈnyĭsh [key], city (1989 pop. 887,000), capital of Voronezh region, central European Russia, on the Voronezh River. A river port and a major industrial center in a black-earth ag...

Carter, Ashton Baldwin

(Encyclopedia)Carter, Ashton Baldwin, 1954–, U.S. political scientist and government official, b. Philadephia, Pa. Trained as a theoretical physicist, he shifted to the study of ballistic missiles and internation...

Cedar Rapids

(Encyclopedia)Cedar Rapids, city (2020 pop. 137,710), seat of Linn co., E central Iowa, on the Cedar River; inc. as a city 1856. The second largest city in Iowa, it i...

guided missile

(Encyclopedia)guided missile, self-propelled, unmanned space or air vehicle carrying an explosive warhead. Its path can be adjusted during flight, either by automatic self-contained controls or remote human control...

atom

(Encyclopedia)CE5 Bohr-Rutherford atom CE5 Probability distribution of the electron in the hydrogen atom: A. Ground state B. Highly excited state atom [Gr.,=uncuttable (indivisible)], basic unit of matte...

relativity

(Encyclopedia)relativity, physical theory, introduced by Albert Einstein, that discards the concept of absolute motion and instead treats only relative motion between two systems or frames of reference. One consequ...

star

(Encyclopedia)star, hot incandescent sphere of gas, held together by its own gravitation, and emitting light and other forms of electromagnetic radiation whose ultimate source is nuclear energy. The universe co...

radiation sickness

(Encyclopedia)radiation sickness, harmful effect produced on body tissues by exposure to radioactive substances. The biological action of radiation is not fully understood, but it is believed that a disturbance in ...

submarine

(Encyclopedia)submarine, naval craft capable of operating for an extended period of time underwater. Submarines are almost always warships, although a few are used for scientific, business, or other purposes (see a...