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electromagnet

(Encyclopedia)CE5 Electromagnet electromagnet, device in which magnetism is produced by an electric current. Any electric current produces a magnetic field, but the field near an ordinary straight conductor is ...

Draper, John William

(Encyclopedia)Draper, John William, 1811–82, American scientist, philosopher, and historian, b. near Liverpool, England, M.D. Univ. of Pennsylvania, 1836. In 1839 he became professor of chemistry at the Univ. of ...

windmill

(Encyclopedia)windmill, apparatus that harnesses wind power for a variety of uses, e.g., pumping water, grinding corn, driving small sawmills, and driving electrical generators. Windmills were probably not known in...

nutrition

(Encyclopedia)nutrition, study of the materials that nourish an organism and of the manner in which the separate components are used for maintenance, repair, growth, and reproduction. Nutrition is achieved in vario...

solid waste

(Encyclopedia)solid waste, discarded materials other than fluids. In the United States in 1996, nearly 210 million tons—about 4.3 lb. (2 kg) per person daily (up from 2.7 lb./1.2 kg in 1960)—were collected and ...

torpedo , in naval warfare

(Encyclopedia)torpedo, in naval warfare, a self-propelled submarine projectile loaded with explosives, used for the destruction of enemy ships. Although there were attempts at subsurface warfare in the 16th and 17t...

Cromwell, Richard

(Encyclopedia)Cromwell, Richard, 1626–1712, lord protector of England; third son of Oliver Cromwell. He was the eldest surviving son at the death of his father (Sept. 3, 1658), who had nominated him as his succes...

Cherenkov, Pavel Alekseyevich

(Encyclopedia)Cherenkov, Pavel Alekseyevich päˈvĭl əlyĭksyāˈyəvĭch chərĕngˈkəf [key], 1904–90, Soviet physicist. He shared with the Soviet physicists I. M. Frank and I. Y. Tamm the 1958 Nobel Prize i...

Evatt, Herbert Vere

(Encyclopedia)Evatt, Herbert Vere vĭr ĕvˈət [key], 1894–1965, Australian statesman. He became (1940) a Labor member of the House of Representatives, before being appointed (1941) attorney general and then min...

amplitude

(Encyclopedia)amplitude ămˈplĭto͞odˌ [key], in physics, maximum displacement from a zero value or rest position. In the harmonic motion of a pendulum, the amplitude of the swing is the greatest distance reache...