10 résultats pour "conductor"
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Richard Wagner
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INTRODUCTION
Richard Wagner (1813-1883), German composer, conductor, and essayist, one of the most influential cultural figures of the 19th century.
May 1864 he was summoned to Munich by the 18-year-old King Ludwig II of Bavaria, who settled Wagner's debts, paid him a generous allowance, and provided himwith housing. Wagner was soon joined in his new home by Cosima von Bülow, Liszt’s daughter and the wife of German conductor and pianist Hans von Bülow. Wagnerand Cosima began a relationship that produced three children before the dissolution of the Bülows' marriage in 1870. Mounting hostility toward Wagner by members ofLudwig’s court resulted...
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Electricidad - ciencia y tecnologia.
forma, las varillas adquieren cargas del mismo signo. Si se cuelga una varilla de un hilo de forma que pueda girar y se le acerca laotra, la primera gira alejándose de la segunda, lo que demuestra que las cargas se repelen. Si las dos varillas tuvieran cargas designo opuesto, la primera se acercaría a la segunda, puesto que las cargas de distinto signo se atraen.© Microsoft Corporation. Reservados todos los derechos. El primer fenómeno eléctrico artificial que se observó fue la propiedad que pre...
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Electricity
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INTRODUCTION
Electricity, one of the basic forms of energy.
electrons in the neutral object are attracted to the positive object. Some of these electrons flow to the side of the neutral object that is nearest to the positive object.This side of the neutral object accumulates electrons and becomes negatively charged. Because electrons leave the far side of the neutral object while its protonsremain stationary, that side becomes positively charged. Since the negatively charged side of the neutral object is closest to the positive object, the attraction bet...
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Motores y generadores eléctricos - ciencia y tecnologia.
velocidad de los motores de corriente continua puede controlarse mediante la variación de la corriente del campo. 4 GENERADORES DE CORRIENTE ALTERNA (ALTERNADORES) Como se decía antes, un generador simple sin conmutador producirá una corriente eléctrica que cambia de sentido a medida que gira la armadura. Este tipo de corrientealterna es ventajosa para la transmisión de potencia eléctrica, por lo que la mayoría de los generadores eléctricos son de este tipo. En su forma más simple, un generador...
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Electric Motors and Generators.
the armature. It is often desirable to generate as high a voltage as possible, and rotating armatures are not practical in such applications because of the possibility of sparkingbetween brushes and slip rings and the danger of mechanical failures that might cause short circuits. Alternators are therefore constructed with a stationary armaturewithin which revolves a rotor composed of a number of field magnets. The principle of operation is exactly the same as that of the AC generator described,...
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¿Qué son las plantas?
células reproductoras llamadas esporas, que no se unen a ninguna otra célula. Cuando las esporas caen al suelo, germinan y desarrollan una nueva planta. ¿CUÁLES SON LOS PRINCIPALES GRUPOS DE PLANTAS? Como ya has visto, las plantas necesitan transportar el alimento, el agua y las sales minerales de una parte a otra de la planta. Pararealizar este transporte, algunas plantas presentan un sistema de tubos o vasos conductores, denominado sistema vascular. Son las llamadas plantas vasculares o...
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Electronics.
electronic circuits. The resistors are made from carbon mixtures, metal films, or resistance wire and have two connecting wires attached. Variable resistors, with anadjustable sliding contact arm, are often used to control volume on radios and television sets. E Capacitors Capacitors consist of two metal plates that are separated by an insulating material ( see Capacitor). If a battery is connected to both plates, an electric charge will flow for a short time and accumulate on each plate. If th...
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Vegetal - ciencias de la naturaleza.
Reino VegetalLas plantas aportan a la atmósfera el oxígeno necesario para la vida y los seres humanos extraen de ellas alimentos, medicamentos,fibras y gran número de otros productos valiosos. El reino Vegetal se divide en 4 grupos o divisiones principales. La división Bryophytaengloba a hepáticas, musgos y antocerotas. Son plantas generalmente de pequeño tamaño en las que la generación dominantecorresponde al gametofito. La división Pteridophyta engloba a helechos y grupos afines los cuales pre...
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American Music
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INTRODUCTION
American Music, the folk, popular, and classical music of the United States--created by American-born or American-trained composers, or originating in American
culture, or written primarily for American audiences.
The country's first permanent orchestra was the New York Philharmonic Society, founded in 1842. Among the first symphonic and operatic composers the mostprominent was William Henry Fry, who composed the first opera by an American ( Leonora, 1845). Fry is best remembered, however, for four symphonies written in the 1850s and 1860s. George F. Bristow wrote the first opera on an American theme; his Rip Van Winkle was performed in New York City in 1855. Town bands, a popular form of community mu...
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Nanotechnology.
ever-finer method of reducing material to the nanoscale size. Instead, nanostructures would be assembled atom by atom and molecule by molecule, from the atomiclevel up, just as occurs in nature. However, assembly at this scale has its own challenges. In school, children learn about some of these challenges when they study the random Brownian motion seen in particles suspended in liquids such as water. Theparticles themselves are not moving. Rather, the water molecules that surround the particles...