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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...

Blackett, Patrick Maynard Stuart

(Encyclopedia)Blackett, Patrick Maynard Stuart blăkˈĭt [key], 1897–1974, English physicist. He was professor of physics at the Univ. of Manchester (1937–53) and in 1953 became professor at the Univ. of Londo...

Port Radium

(Encyclopedia)Port Radium, mining village, N central Northwest Territories, Canada, on Great Bear Lake. The mines were discovered in 1930 and yielded deposits of pitchblende, from which much radium was produced. Du...

electron-volt

(Encyclopedia)electron-volt, abbr. eV, unit of energy used in atomic and nuclear physics; 1 electron-volt is the energy transferred in moving a unit charge, positive or negative and equal to that charge on the elec...

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...

fission

(Encyclopedia)fission, in physics: see nuclear energy and nucleus; see also atomic bomb. ...

hydrogen bomb

(Encyclopedia)hydrogen bomb or H-bomb, weapon deriving a large portion of its energy from the nuclear fusion of hydrogen isotopes. In an atomic bomb, uranium or plutonium is split into lighter elements that togethe...

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...

maser

(Encyclopedia)maser māˈzər [key], device for creation, amplification, and transmission of an intense, highly focused beam of high-frequency radio waves. The name maser is an acronym for microwave amplification b...

Szilard, Leo

(Encyclopedia)Szilard, Leo sĭˈlärd [key], 1898–1964, American nuclear physicist and biophysicist, born in Hungary. He was educated at the Budapest Institute of Technology and the Univ. of Berlin, receiving a d...