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loudspeaker

(Encyclopedia)CE5 Electrodynamic loudspeaker loudspeaker or speaker, device used to convert electrical energy into sound. It consists essentially of a thin flexible sheet called a diaphragm that is made to vibr...

North Rhine–Westphalia

(Encyclopedia)North Rhine–Westphalia nôrtˈrīn-vĕstˌfäˈlən [key], state (1994 pop. 17,759,000), 13,111 sq mi (33,957 sq km), W central Germany. Düsseldorf is the capital. The state is bounded by Belgium a...

livermorium

(Encyclopedia)livermorium, artificially produced radioactive chemical element; symbol Lv; at. no. 116; mass number of most stable isotope 292; m.p., b.p., sp. gr., and valence unknown. Situated in Group 16 of the p...

lamp

(Encyclopedia)lamp, originally a vessel for holding oil or some combustible substance that could be burned through a wick for illumination; the term has been extended to other lighting devices. Stones, shells, and ...

carbohydrate

(Encyclopedia)carbohydrate, any member of a large class of chemical compounds that includes sugars, starches, cellulose, and related compounds. These compounds are produced naturally by green plants from carbon dio...

supercomputer

(Encyclopedia)supercomputer, a state-of-the-art, extremely powerful computer capable of manipulating massive amounts of data in a relatively short time. Supercomputers are very expensive and are employed for specia...

Teller, Edward

(Encyclopedia)Teller, Edward, 1908–2003, American physicist, b. Budapest, Hungary, Ph.D. Univ. of Leipzig, 1930, where he studied under Werner Heisenberg. Fleeing the Nazis, he came to the United States in 1935 a...

Wells, H. G.

(Encyclopedia)Wells, H. G. (Herbert George Wells), 1866–1946, English author. Although he is probably best remembered for his works of science fiction, he was also an imaginative social thinker, working assiduous...

boiling point

(Encyclopedia)boiling point, temperature at which a substance changes its state from liquid to gas. A stricter definition of boiling point is the temperature at which the liquid and vapor (gas) phases of a substanc...

quasar

(Encyclopedia)quasar kwāˈsär [key], one of a class of blue celestial objects having the appearance of stars when viewed through a telescope and currently believed to be the most distant and most luminous objects...