15 résultats pour "observers"
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Relativity
I
INTRODUCTION
Albert Einstein
In 1905 German-born American physicist Albert Einstein published his first paper outlining the theory of relativity.
in calculating very large distances or very large aggregations of matter. As the quantum theory applies to the very small, so the relativity theory applies to the verylarge. Until 1887 no flaw had appeared in the rapidly developing body of classical physics. In that year, the Michelson-Morley experiment, named after the American physicistAlbert Michelson and the American chemist Edward Williams Morley, was performed. It was an attempt to determine the rate of the motion of the earth through t...
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Relativity - astronomy.
beta, for example, might be as large as 0.5, and the mass of the electron doubled. The mass of a rapidly moving electron could be easily determined by measuring thecurvature produced in its path by a magnetic field; the heavier the electron, the greater its inertia and the less the curvature produced by a given strength of field ( see Magnetism). Experimentation dramatically confirmed Einstein's prediction; the electron increased in mass by exactly the amount he predicted. Thus, the kinetic ener...
- Seven Wonders of the World Seven Wonders of the World, works of art and architecture regarded by ancient Greek and Roman observers as the most extraordinary structures of antiquity.
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Meteor Shower - astronomy.
Meteor observations with radar work much the same way that observations with radio forward scattering observations do. With radar, the receiver and transmitter areat the same place. Both methods provide numbers of meteors per hour, without the visual observer’s dependence on a clear, dark sky. Astronomers can determine the orbit of the particle stream that creates a meteor shower by finding out the radiant of the shower and the speed of the meteors.Observers must record meteors with cameras or v...
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Extreme Sports.
racing events are the Raid Gauloises and the Eco-Challenge. Created in 1989 by French journalist Gerard Fusil, the Raid Gauloises is a grueling two-week adventure racein which five-person teams cross rugged and remote terrain. The inaugural Raid was held in New Zealand, and subsequent races have been staged in Costa Rica,Madagascar, Borneo, and Chile. The race has five separate stages designed to fit each location’s unique terrain. Stages may require horseback riding, white-waterpaddling, mounta...
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Gravitation
I
INTRODUCTION
Gravitation, the force of attraction between all objects that tends to pull them toward one another.
precise observations possible, and Galileo was one of the first to use a telescope to study astronomy. In 1609 Galileo observed that moons orbited the planet Jupiter, afact that could not reasonably fit into an earth-centered model of the heavens. The new heliocentric theory changed scientists' views about the earth's place in the universe and opened the way for new ideas about the forces behind planetarymotion. However, it was not until the late 17th century that Isaac Newton developed a theory...
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Gravitation - astronomy.
precise observations possible, and Galileo was one of the first to use a telescope to study astronomy. In 1609 Galileo observed that moons orbited the planet Jupiter, afact that could not reasonably fit into an earth-centered model of the heavens. The new heliocentric theory changed scientists' views about the earth's place in the universe and opened the way for new ideas about the forces behind planetarymotion. However, it was not until the late 17th century that Isaac Newton developed a theory...
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Arab-Israeli Conflict.
the Suez Canal and in 1951 blockaded the Strait of Tiran (Israel’s access to the Red Sea), which Israel regarded as an act of war. In June 1956 Egypt nationalized theSuez Canal, which had been jointly owned by Britain and France. In late October, Israel invaded the Gaza Strip and Sinai Peninsula, defeating Egyptian forces there.Britain and France attacked Egypt a few days later. Although the fighting was brief and Israel eventually withdrew from the Sinai and Gaza, the conflict furtherexacerbate...
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Arab-Israeli Conflict - History.
the Suez Canal and in 1951 blockaded the Strait of Tiran (Israel’s access to the Red Sea), which Israel regarded as an act of war. In June 1956 Egypt nationalized theSuez Canal, which had been jointly owned by Britain and France. In late October, Israel invaded the Gaza Strip and Sinai Peninsula, defeating Egyptian forces there.Britain and France attacked Egypt a few days later. Although the fighting was brief and Israel eventually withdrew from the Sinai and Gaza, the conflict furtherexacerbate...
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George Bush.
1986 it was folded into Harken Energy Corporation, another Texas petroleum company. Bush served as a consultant and a member of Harken’s board of directors. In 1987 Bush relocated his family to Washington, D.C., to assist his father in his bid to become president. He worked as a campaign adviser at his father’s nationalcampaign headquarters, serving as a liaison to the media and to conservative and Christian leaders. He was a trusted confidant of his father and mother, whosometimes dispatched Bu...
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George Bush - USA History.
1986 it was folded into Harken Energy Corporation, another Texas petroleum company. Bush served as a consultant and a member of Harken’s board of directors. In 1987 Bush relocated his family to Washington, D.C., to assist his father in his bid to become president. He worked as a campaign adviser at his father’s nationalcampaign headquarters, serving as a liaison to the media and to conservative and Christian leaders. He was a trusted confidant of his father and mother, whosometimes dispatched Bu...
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Persian Gulf War.
to “use all necessary means” to force Iraq from Kuwait if Iraq remained in the country after January 15, 1991. The Iraqis rejected the ultimatum. Soon after the vote,the United States agreed to a direct meeting between Secretary of State James Baker and Iraq’s foreign minister. The two sides met on January 9. Neither offered tocompromise. The United States underscored the ultimatum, and the Iraqis refused to comply with it, even threatening to attack Israel. For the United States, themeeting was...
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Persian Gulf War - History.
to “use all necessary means” to force Iraq from Kuwait if Iraq remained in the country after January 15, 1991. The Iraqis rejected the ultimatum. Soon after the vote,the United States agreed to a direct meeting between Secretary of State James Baker and Iraq’s foreign minister. The two sides met on January 9. Neither offered tocompromise. The United States underscored the ultimatum, and the Iraqis refused to comply with it, even threatening to attack Israel. For the United States, themeeting was...
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Persian Gulf War - U.
to “use all necessary means” to force Iraq from Kuwait if Iraq remained in the country after January 15, 1991. The Iraqis rejected the ultimatum. Soon after the vote,the United States agreed to a direct meeting between Secretary of State James Baker and Iraq’s foreign minister. The two sides met on January 9. Neither offered tocompromise. The United States underscored the ultimatum, and the Iraqis refused to comply with it, even threatening to attack Israel. For the United States, themeeting was...
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Social Psychology.
During the 1960s, American psychologist Stanley Milgram studied a form of social influence stronger than conformity: obedience to authority. In a famous series ofexperiments that attracted controversy about human research ethics, Milgram put each of 1,000 subjects into a situation in which they were ordered by anexperimenter to administer painful electric shocks to a confederate (who did not actually receive any shocks). The subjects in these studies were led to believe that theywere acting as '...