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power, electric

(Encyclopedia)power, electric, energy dissipated in an electrical or electronic circuit or device per unit of time. The electrical energy supplied by a current to an appliance enables it to do work or provide some ...

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 ...

environmentalism

(Encyclopedia)environmentalism, movement to protect the quality and continuity of life through conservation of natural resources, prevention of pollution, and control of land use. The philosophical foundations for ...

lead, chemical element

(Encyclopedia)lead, metallic chemical element; symbol Pb [Lat. plumbum]; at. no. 82; at. wt. 207.2; m.p. 327.502℃; b.p. about 1,740℃; sp. gr. 11.35 at 20℃; valence +2 or +4. One of the oldest metals used by h...

interference

(Encyclopedia)CE5 Constructive interference: Two crests or two troughs meet and combine (A, B, C). Destructive interference: A crest and a trough meet and cancel each other (D, E, F). interference, in physics, ...

observatory

(Encyclopedia)observatory, scientific facility especially equipped to detect and record naturally occurring scientific phenomena. Although geological and meteorological observatories exist, the term is generally ap...

art conservation and restoration

(Encyclopedia)art conservation and restoration, the preservation of structurally sound works of art, the halting of processes that lead to the damage of works of art, and the repair of already damaged works of art....

star

(Encyclopedia)star, hot incandescent sphere of gas, held together by its own gravitation, and emitting light and other forms of electromagnetic radiation whose ultimate source is nuclear energy. The universe co...

global warming

(Encyclopedia)global warming, the gradual increase of the temperature of the earth's lower atmosphere as a result of the increase in greenhouse gases since the Industrial Revolution. Global warming and its effects,...

lighting

(Encyclopedia)CE5 Incandescent lamp CE5 Basic fluorescent lamp lighting, light produced by artificial means to allow visibility in enclosures and at night. For stage lighting, see scene design and stage ligh...