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cathode-ray tube

(Encyclopedia)CE5 Cathode-ray tube cathode-ray tube (CRT), special-purpose electron tube in which electrons are accelerated by high-voltage anodes, formed into a beam by focusing electrodes, and projected towar...

causality

(Encyclopedia)causality, in philosophy, the relationship between cause and effect. A distinction is often made between a cause that produces something new (e.g., a moth from a caterpillar) and one that produces a c...

earthquake

(Encyclopedia)CE5 Worldwide pattern of earthquake activity: The dots indicate the epicenters of all earthquakes recorded during a recent 10-year period. CE5 earthquake, trembling or shaking movement of the ea...

calculus

(Encyclopedia)CE5 The derivative f″(x) of the function f(x) at the point P represents the slope of the tangent line at that point. CE5 The area under the curve y=f(x) may be found by calculating the sum of ...

Coco

(Encyclopedia)Coco, river, c.466 mi (750 km) long, rising in S Honduras and flowing E into Nicaragua and then NE to the Caribbean Sea. Part of the Mosquito Coast region, and once the object of dispute between Hondu...

sintering

(Encyclopedia)sintering, process of forming objects from a metal powder by heating the powder at a temperature below its melting point. In the production of small metal objects it is often not practical to cast the...

Vyazma

(Encyclopedia)Vyazma vyäzˈmə [key], city (1989 pop. 59,000), N central European Russia, on the Vyazma River, a tributary of the Dnieper. Founded in the 9th cent., Vyazma became an important trade and military ce...

trigonometry

(Encyclopedia)trigonometry [Gr.,=measurement of triangles], a specialized area of geometry concerned with the properties of and relations among the parts of a triangle. Spherical trigonometry is concerned with the ...

isomer

(Encyclopedia)isomer īˈsəmər [key], in chemistry, one of two or more compounds having the same molecular formula but different structures (arrangements of atoms in the molecule). Isomerism is the occurrence of ...

idol

(Encyclopedia)idol, an object, frequently an image, which is worshiped as a deity. Idols are usually found in human or animal form and may be treated as though alive; they are fed, bathed, anointed, crowned, and so...