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watt

(Encyclopedia)watt [for James Watt], abbr. W, unit of power, or work done per unit time, equal to 1 joule per second. It is used as a measure of electrical and mechanical power. One watt is the amount of power that...

commutator

(Encyclopedia)commutator, device used in an electric generator to convert the alternating current produced in the generator into direct current before the current is sent into an external circuit; it is basically a...

Mark, Gospel according to

(Encyclopedia)Mark, Gospel according to, 2d book of the New Testament. The shortest of the four Gospels and probably the earliest, it is usually thought to have been composed shortly before the destruction of the T...

mass spectrograph

(Encyclopedia)mass spectrograph, device used to separate electrically charged particles according to their masses; a form of the instrument known as a mass spectrometer is often used to measure the masses of isotop...

governor, device

(Encyclopedia)governor, automatic device used to regulate and control such variables as speed or pressure in the functioning of an engine or other machine. A governor may be an electric, hydraulic, or mechanical de...

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 ...

handball, team

(Encyclopedia)handball, team, or field handball, team court game. Despite its status as an Olympic sport, the game is virtually unknown in the United States. Originated in central Europe in the early 1900s as an ou...

reggae

(Encyclopedia)reggae, Jamaican popular music that developed in the 1960s among Kingston's poor blacks, drawing on American “soul” music and traditional African and Jamaican folk music and ska (a Jamaican and Br...

welding

(Encyclopedia)welding, process for joining separate pieces of metal in a continuous metallic bond. Cold-pressure welding is accomplished by the application of high pressure at room temperature; forge welding (forgi...

Moissan, Henri Ferdinand Frederick

(Encyclopedia)Moissan, Henri Ferdinand Frederick, 1852–1907, French chemist, Ph.D. École Pratique des Haute Études, Paris, 1880. Moissan was a professor at the School of Pharmacy in Paris (1886–1900) and at t...