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fatigue, in physiology
(Encyclopedia)fatigue, in physiology, inability to perform reasonable and necessary physical or mental activity. Muscle fatigue, for example, results when the contractile properties of muscle are reduced, and conti...Zuma, Jacob Gedleyihlekisa
(Encyclopedia)Zuma, Jacob Gedleyihlekisa, 1942–, South African political leader, b. Indkandla, Natal (now KwaZulu-Natal) prov. Zuma received no formal schooling and joined the African National Congress (ANC) when...generator
(Encyclopedia) CE5 Generator: The rotation of the conducting coil of wire in a magnetic field causes a current to be induced in the coil. This current is alternating and is conducted from the coil by means of sli...physical chemistry
(Encyclopedia)physical chemistry, branch of science that combines the principles and methods of physics and chemistry. It provides a fundamental theoretical and experimental basis for all of chemistry, including or...semiconductor
(Encyclopedia) CE5 N-type and P-type crystals: In a pure silicon crystal each silicon atom (Si) is surrounded by four valence electrons. In the N-doped semiconductor, illustrated in the left-hand figure, some sil...Mach's principle
(Encyclopedia)Mach's principle mäks [key] [for E. Mach], assertion that the inertial effects of mass are not innate in a body, but arise from its relation to the totality of all other masses, i.e., to the universe...Galvani, Luigi
(Encyclopedia)Galvani, Luigi lo͞oēˈjē gälväˈnē [key], 1737–98, Italian physician. He was professor of anatomy from 1775 at the Univ. of Bologna and was noted as a surgeon and for research in comparative a...installment buying and selling
(Encyclopedia)installment buying and selling, buying and selling of goods on credit, with the stipulation that payments shall be made at specified intervals in set amounts. The goods may be used by the buyer before...solar energy
(Encyclopedia)solar energy, any form of energy radiated by the sun, including light, radio waves, and X rays, although the term usually refers to the visible light of the sun. Solar energy is needed by green plants...electromagnetic radiation
(Encyclopedia) CE5 Electromagnetic spectrum electromagnetic radiation, energy radiated in the form of a wave as a result of the motion of electric charges. A moving charge gives rise to a magnetic field, and if ...Browse by Subject
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