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pole, in electricity and magnetism

(Encyclopedia)pole, in electricity and magnetism, point where electric or magnetic force appears to be concentrated. A single electric charge located at a point is sometimes referred to as an electric monopole. An ...

Autolycus, Greek astronomer and mathematician

(Encyclopedia)Autolycus ôtŏlˈĭkəs [key], fl. 4th cent. b.c., astronomer and mathematician of Pitane in Aeolis. Of his two extant works, that on the revolving sphere is said to be the oldest completely preserve...

trachoma

(Encyclopedia)trachoma trəkōˈmə [key], infection of the mucous membrane of the eyelids caused by the bacterium Chlamydia trachomatis. Trachoma affects at least 86 million people worldwide. An estimated 1.9 mill...

Jhelum, river, India and Pakistan

(Encyclopedia)Jhelum or Jehlam both: jāˈləm [key], westernmost of the five rivers of the Punjab, 480 mi (772 km) long. Rising in Jammu and Kashmir, India, it flows W through the Vale of Kashmir, S through Pakist...

riot, rout, and unlawful assembly

(Encyclopedia)riot, rout, and unlawful assembly, in law, varying degrees of concerted disturbance of the peace. At common law, an unlawful assembly is a gathering of at least three persons whose conduct causes obse...

Peng Dehuai

(Encyclopedia)Peng Dehuai or P'eng Teh-huai both: pŭngˈ dŭˈhwīˈ [key], 1898–1974, Communist Chinese general and political leader. He held various command positions in the Red Army, and in 1934–35 he joine...

Narva, river, Estonia and Russia

(Encyclopedia)Narva, river, c.50 mi (80 km) long, rising in Lake Peipus (Chudskoye), E Estonia, and flowing northeast past the city of Narva into the Gulf of Finland. It forms the border between Estonia and Russia....

centripetal force and centrifugal force

(Encyclopedia)CE5 Centripetal and centrifugal forces: When a ball is swung in a circle at the end of a string, centripetal and centrifugal forces act as shown above. centripetal force and centrifugal force, act...

Paraguay, river, Brazil and Paraguay

(Encyclopedia)Paraguay, river, c.1,300 mi (2,090 km) long, rising in the highlands of central Mato Grosso state, Brazil. Flowing generally southward, it forms the border between Brazil and Paraguay in the pantanal,...