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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...International Atomic Energy Agency
(Encyclopedia)International Atomic Energy Agency: see Atomic Energy Agency, International. ...nucleus, in physics
(Encyclopedia)nucleus, in physics, the extremely dense central core of an atom. Following the discovery of radioactivity by A. H. Becquerel in 1896, Ernest Rutherford identified two types of radiation given off b...Archimedes' principle
(Encyclopedia)Archimedes' principle, principle that states that a body immersed in a fluid is buoyed up by a force equal to the weight of the displaced fluid. The principle applies to both floating and submerged bo...snowmobile
(Encyclopedia)snowmobile, vehicle designed to travel over snow, ice, and similar surfaces that offer limited traction and weight-supporting capability. As the performance of the vehicle depends to a large extent on...balance
(Encyclopedia)balance, instrument used in laboratories and pharmacies to measure the mass or weight of a body. A balance functions by measuring the force of gravity that the earth exerts on an object, i.e., its wei...number-average molecular weight
(Encyclopedia)number-average molecular weight: see molecular weight. ...Oak Ridge
(Encyclopedia)Oak Ridge, city (1990 pop. 27,310), Anderson and Roane counties, E Tenn., on Black Oak Ridge and the Clinch River; founded by the U.S. government 1942, inc. as an independent city 1959. For years Oak ...mole, in chemistry
(Encyclopedia)mole, in chemistry, a quantity of particles of any type equal to Avogadro's number, or 6.02×1023 particles. One gram-molecular weight of any molecular substance contains exactly one mole of molecules...Oppenheimer, J. Robert
(Encyclopedia)Oppenheimer, J. Robert ŏpˈənhīˌmər [key], 1904–67, American physicist, b. New York City, grad. Harvard (B.A., 1925), Ph.D. Univ. of Göttingen, 1927. He taught at the Univ. of California and t...Browse by Subject
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