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resistor

(Encyclopedia)resistor, two-terminal electric circuit component that offers opposition to an electric current. Resistors are normally designed and operated so that, with varying levels of current, variations of the...

Abdullah, Abdullah

(Encyclopedia)Abdullah, Abdullah äbdəläˈ äbdəläˈ [key], 1960–, Afghan political leader. An ophthalmologist of Tajik and Pashtun ethnicity, he worked with guerrilla leader Ahmed Shah Massoud, head of the N...

cube

(Encyclopedia)cube, in geometry, regular solid bounded by six equal squares. All adjacent faces of a cube are perpendicular to each other; any one face of a cube may be its base. The dimensions of a cube are the le...

Kagame, Paul

(Encyclopedia)Kagame, Paul kägäˈmə [key], 1957–, Rwandan political leader. Kagame was born into a Tutsi family that fled (1960) ethnic violence in Rwanda. Raised in Uganda, he became a member of Yoweri Museve...

Sorel, Georges

(Encyclopedia)Sorel, Georges sôrĕlˈ [key], 1847–1922, French social philosopher. An engineer before he devoted himself to writing, Sorel found in the political and social life of bourgeois democracy the trium...

Agrippina the Younger

(Encyclopedia)Agrippina the Younger, d. a.d. 59, Roman matron; daughter of Germanicus Caesar and Agrippina the Elder. By her first husband, Cneius Domitius Ahenobarbus, she was the mother of Nero. After her brother...

Yang Kuei-fei

(Encyclopedia)Yang Kuei-fei yäng gwā-fā [key], 719–56, concubine of the T'ang emperor Hsüan-tsung. The most famous beauty in Chinese history, in legend she is said to have captivated the emperor who then negl...

Adolf of Nassau

(Encyclopedia)Adolf of Nassau näˈsou [key], d. 1298, duke of Luxembourg, German king (1292–98). He owed his election to the ecclesiastical electors, who, fearing the growing power and ambition of the Hapsburgs,...

Aetolian League

(Encyclopedia)Aetolian League, confederation centering in the cities of Aetolia. It was formed in the 4th cent. b.c. and began to gain power in the 3d cent. in opposing the Achaean League and the Macedonians. At it...

chain

(Encyclopedia)chain, flexible series of connected links used in various ways, especially for the transmission of motive power, for hoisting (see pulley), and for securing or fastening. Commonly, mechanical energy f...