Columbia Encyclopedia

Search results

500 results found

radio frequency

(Encyclopedia)radio frequency, range of electromagnetic waves with a frequency or wavelength suitable for communication uses. Some of these waves serve as carriers of the lower-frequency audio waves; others are mod...

satellite, artificial

(Encyclopedia)CE5 A. Nimbus weather satellite B. Syncom communications satellite satellite, artificial, object constructed by humans and placed in orbit around the earth or other celestial body (see also space ...

microscope

(Encyclopedia)CE5 Compound microscope microscope, optical instrument used to increase the apparent size of an object. The electron microscope, which is not limited by the powers of optical lenses and light,...

Albany, cities, United States

(Encyclopedia)Albany 1, 3, 4 ôlˈbənē; 2 ôlˈbĕnˌē, ălbāˈnē [key]. 1 Residential city (2020 pop. 20,271), Alameda co., W Calif., on the eastern shore of San Francisco...

Volgograd

(Encyclopedia)Volgograd vôlgəgrätˈ [key], formerly Stalingrad, city (1989 pop. 999,000), capital of Volgograd region, SE European Russia, a port on the Volga River and the eastern terminus of the Volga-Don Cana...

pulley

(Encyclopedia)CE5 Pulleys: The mechanical advantage (MA) of a system of pulleys is equal to the number of supporting strands: in A MA=1 and in B MA=2. pulley, simple machine consisting of a wheel over which a r...

rhyme

(Encyclopedia)rhyme or rime, the most prominent of the literary artifices used in versification. Although it was used in ancient East Asian poetry, rhyme was practically unknown to the ancient Greeks and Romans. Wi...

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 ...

electronics

(Encyclopedia)electronics, science and technology based on and concerned with the controlled flow of electrons or other carriers of electric charge, especially in semiconductor devices. It is one of the principal b...

Coen Brothers

(Encyclopedia)Coen Brothers, American filmmakers Joel Coen, 1955–, and Ethan Coen, 1958–, both b. St. Louis Park, Minn. Joel studied at New York Univ. Film School (B.A., 1978), Ethan at Princeton (B.A., 1979). ...