Columbia Encyclopedia

Search results

500 results found

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...

bibliography

(Encyclopedia)bibliography. The listing of books is of ancient origin. Lists of clay tablets have been found at Nineveh and elsewhere; the library at Alexandria had subject lists of its books. Modern bibliography b...

nuclear physics

(Encyclopedia)nuclear physics, study of the components, structure, and behavior of the nucleus of the atom. It is especially concerned with the nature of matter and with nuclear energy. ...

physics

(Encyclopedia)physics, branch of science traditionally defined as the study of matter, energy, and the relation between them; it was called natural philosophy until the late 19th cent. and is still known by this na...

fission

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

barn

(Encyclopedia)barn, abbr. b, in physics, unit of nuclear cross section, i.e., the effective target presented by a nucleus for collisions leading to nuclear reactions; it is equal to 10−24 square centimeters. The ...

field, in physics

(Encyclopedia)field, in physics, region throughout which a force may be exerted; examples are the gravitational, electric, and magnetic fields that surround, respectively, masses, electric charges, and magnets. The...

Browse by Subject