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hydraulic machine

(Encyclopedia)CE5 Hydraulic pressure: In any hydraulic device the pressure exerted by one piston is transmitted throughout the fluid. Since pressure equals force divided by area, a small force (F1) exerted on a ...

nitrogen cycle

(Encyclopedia)CE5 Nitrogen cycle nitrogen cycle, the continuous flow of nitrogen through the biosphere by the processes of nitrogen fixation, ammonification (decay), nitrification, and denitrification. Nitrogen...

laissez-faire

(Encyclopedia)laissez-faire lĕsˌā fârˈ [key] [Fr.,=leave alone], in economics and politics, doctrine that an economic system functions best when there is no interference by government. It is based on the belie...

Shaw, George Bernard

(Encyclopedia)Shaw, George Bernard, 1856–1950, Irish playwright and critic. He revolutionized the Victorian stage, then dominated by artificial melodramas, by presenting vigorous dramas of ideas. The lengthy pref...

volcano

(Encyclopedia)volcano, vents or fissures in the earth's crust through which gases, molten rock, or lava, and solid fragments are discharged. Their study is called volcanology. The term volcano is commonly applied b...

classification

(Encyclopedia)CE5 classification, in biology, the systematic categorization of organisms into a coherent scheme. The original purpose of biological classification, or systematics, was to organize the vast number...

Antarctica

(Encyclopedia)CE5 Antarctica ăntärkˈtĭkə, –ärˈtĭkə [key], the fifth largest continent, c.5,500,000 sq mi (14,245,000 sq km), asymmetrically centered on the South Pole and almost entirely within the An...

Arab Spring

(Encyclopedia)Arab Spring, in modern North African and Middle Eastern history, antigovernment demonstrations and uprisings that, from late 2010, swept many of the regions' Arab nations. Arising in large part in rea...

Pluto, in astronomy

(Encyclopedia)Pluto, in astronomy, a dwarf planet and the first Kuiper belt, or transneptunian, object (see comet) to be discovered (1930) by astronomers. Pluto has an elliptical orbit usually lying beyond that of ...

ring, in astronomy

(Encyclopedia)ring, in astronomy, relatively thin band of rocks and dust and ice particles that orbit around a planet in the planet's equatorial plane. All four of the giant planets in the solar system—Jupiter, S...