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Semipalatinsk Test Site

(Encyclopedia)Semipalatinsk Test Site, Soviet nuclear testing site, c.6,950 sq mi (18,000 sq km), NE Kazakhstan, near the city of Kurchatov and some 90 mi (150 km) W of Semey (formerly Semipalatinsk). Between 1949 ...

laser

(Encyclopedia)CE5 Ordinary light sources produce incoherent light, while a laser produces a beam of coherent light. laser [acronym for light amplification by stimulated emission of radiation], device for the cr...

ecology

(Encyclopedia)ecology, study of the relationships of organisms to their physical environment and to one another. The study of an individual organism or a single species is termed autecology; the study of groups of ...

mass, in physics

(Encyclopedia)mass, in physics, the quantity of matter in a body regardless of its volume or of any forces acting on it. The term should not be confused with weight, which is the measure of the force of gravity (se...

sonar

(Encyclopedia)sonar sōˈnär [key], device used underwater for locating submerged objects and for submarine communication by means of sound waves. The term sonar is an acronym for sound navigation ranging. The mai...

Ovshinsky, Stanford Robert

(Encyclopedia)Ovshinsky, Stanford Robert, 1922–2012, American inventor and scientist, b. Akron, Ohio. Self-taught, he developed a new type of lathe in the 1940s, the first of many innovations and patents. Special...

Zeeman effect

(Encyclopedia)Zeeman effect, splitting of a single spectral line (see spectrum) into a group of closely spaced lines when the substance producing the single line is subjected to a uniform magnetic field. The effect...

Bernoulli's principle

(Encyclopedia)CE5 Bernoulli's principle Bernoulli's principle, physical principle formulated by Daniel Bernoulli that states that as the speed of a moving fluid (liquid or gas) increases, the pressure within th...

Murmansk

(Encyclopedia)Murmansk mo͝ormänskˈ [key], city (1989 pop. 468,000), capital of Murmansk region, NW European Russia, on the Kola Gulf of the Barents Sea. It is the terminus of the Northeast Passage and the world'...

Chu, Steven

(Encyclopedia)Chu, Steven, 1948–, U.S. physicist and government official, b. St. Louis, Mo., grad. Univ. of Rochester (B.S., A.B. 1970), Univ. of California, Berkeley (Ph.D. 1976). He worked from 1978 at Bell Lab...