(Encyclopedia) specific heat, ratio of the heat capacity of a substance to the heat capacity of a reference substance, usually water. Heat capacity is the amount of heat needed to change the…
(Encyclopedia) Rugby, town (1991 pop. 59,039), Warwickshire, central England. An important railroad junction and engineering center, Rugby is the seat of one of England's most esteemed public schools…
(Encyclopedia) Carlstadt,&sp;KarlstadtKarlstadtboth: kärlˈshtät [key], or KarolostadtCarlstadt,käˈrôlōshtätˌ [key], c.1480–1541, German Protestant reformer, whose original name was Andreas…
(Encyclopedia) mutation, in biology, a sudden, random change in a gene, or unit of hereditary material, that can alter an inheritable characteristic. Most mutations are not beneficial, since any…
(Encyclopedia) induction, in electricity and magnetism, common name for three distinct phenomena. Electromagnetic induction is the production of an electromotive force (emf) in a conductor as a…
(Encyclopedia) James, William, 1842–1910, American philosopher, b. New York City, M.D. Harvard, 1869; son of the Swedenborgian theologian Henry James and brother of the novelist Henry James. In 1872…
(Encyclopedia) magic, in religion and superstition, the practice of manipulating and controlling the course of nature by preternatural means. Magic is based upon the belief that the universe is…
(Encyclopedia) ultraviolet radiation, invisible electromagnetic radiation between visible violet light and X rays; it ranges in wavelength from about 400 to 4 nanometers and in frequency from about…
(Encyclopedia) dielectricdielectricdīˌĭlĕkˈtrĭk [key], material that does not conduct electricity readily, i.e., an insulator (see insulation). A good dielectric should also have other properties: It…
(Encyclopedia) Compton effect [for A. H. Compton], increase in the wavelengths of X rays and gamma rays when they collide with and are scattered from loosely bound electrons in matter. This effect…
