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Tianjin

(Encyclopedia)Tianjin or Tientsin both: tyänˈjĭnˈ [key], city and independent municipality (2010 pop. 12,938,224), NE China. In E central Hebei prov., it is a politically independent unit (4,400 sq mi/11,399 sq...

noise

(Encyclopedia)noise, any signal that does not convey useful information. Electrical noise consists of electrical currents or voltages that interfere with the operation of electronic systems. Electrical noise limits...

horsepower

(Encyclopedia)horsepower, unit of power in the English system of units. It is equal to 33,000 foot-pounds per minute or 550 foot-pounds per second or approximately 746 watts. The term horsepower originated with Jam...

Fredonia

(Encyclopedia)Fredonia frēdōˈnēə [key], village (2020 pop. 9,585), Chautauqua co., SW N.Y., near Lake Erie; ...

Oahe Dam

(Encyclopedia)Oahe Dam ōwäˈhē [key], major unit of the Missouri River basin project, 242 ft (74 m) high and 9,360 ft (2,853 m) long, on the Missouri River, central S.Dak., near Pierre; built 1948–63 by the U....

North Platte project

(Encyclopedia)North Platte project, unit of the U.S. Bureau of Reclamation, in the North Platte River valley, W Nebr. and E Wyo. It supplies hydroelectric power to many towns and industries and provides irrigation ...

Oersted, Hans Christian

(Encyclopedia)Oersted or Ørsted, Hans Christian häns krĭsˈtyän örˈstĭᵺ [key], 1777–1851, Danish physicist and chemist. He was professor at Copenhagen from 1806. His discovery (1819) that a magnetic need...

kilogram

(Encyclopedia)kilogram, abbr. kg, fundamental unit of mass in the metric system, defined as the mass of the International Prototype Kilogram, a platinum-iridium cylinder kept at Sèvres, France, near Paris. Copies ...

solar constant

(Encyclopedia)solar constant, the average amount of radiant energy received by the earth's atmosphere from the sun; its value is about 2 calories per min incident on each square centimeter of the upper atmosphere. ...

jet propulsion

(Encyclopedia)CE5 Types of jet engines: In the propeller-driven turbine a stream of high-velocity gases provides the power to drive the turbine and turn the propeller. In the jet-driven turbine the stream of gas...