field
field in physics, region throughout which a force may be exerted; examples are the gravitational, electric, and magnetic fields that surround, respectively, masses, electric charges, and magnets. The field concept was developed by M. Faraday based on his investigation of the lines of force that appear to leave and return to a magnet at its poles (see flux, magnetic ). Fields are used to describe all cases where two bodies separated in space exert a force on each other. The alternative to postulating a field is to assume that physical influences can be transmitted through empty space without any material or physical agency. Such action-at-a-distance, especially if it occurs instantaneously, violates both common sense and certain modern theories, notably relativity , which posits that nothing can travel faster than light. In a field description, rather than body A directly exerting a force on body B, body A (the source) creates a field in every direction around it and body B (the detector) experiences the field that exists at its position. If a change occurs at the source, its effect propagates outward through the field at a constant speed and is felt at the detector only after a certain delay in time. The field is thus a kind of "middleman" for transmitting forces. Each type of force (electric, magnetic, nuclear, or gravitational) has its own appropriate field; a body experiences the force due to a given field only if the body itself it also a source of that kind of field. The reciprocity implied by Newton's third law of motion (equal action and reaction) is thus preserved. If two bodies exert a mutual force, they possess potential energy that depends on their relative positions; it is natural to regard this energy as residing in the field the bodies create.
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Analysis: Ronald Wilson Reagan's burial ceremony
Transcript from: Weekend Edition - Saturday (NPR); 6/12/2004; ; 700+ words
; ...Edition - Saturday (NPR) 06-12-2004 Analysis: Ronald Wilson Reagan's burial ceremony Host: SCOTT SIMON Time: 12...SIMON, host: After a week of pomp and ceremony, Ronald Wilson Reagan, the 40th president of the United States, reached...
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A suitable remembrance of Ronald Wilson Reagan
Newspaper article from: Indian Country Today (Lakota Times); 7/7/2004; ; 700+ words
; ...able leaders of the 20th century, Ronald Wilson Reagan. As we transition from a period...do so too soon. Nonetheless, Reagan has already been recognized in...and preserves his memory. The Ronald Reagan Legacy Project, headed...
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Speaker's Remarks at the State Funeral of the Late President Ronald Wilson Reagan
Newspaper article from: U.S. Newswire; 6/9/2004; 700+ words
; ...the State Funeral of the late President Ronald Wilson Reagan tonight in the Capitol Rotunda: "Mrs. Reagan, Mr. Vice President, Members of Congress, Distinguished Guests: Ronald Reagan's long journey has finally drawn...
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OBITUARY: Ronald Wilson Reagan.(Features)
Newspaper article from: Daily Post (Liverpool, England); 6/7/2004; 559 words
; ...a parlous state,especially as Reagan had referred to Russia as an...of evil''.And at one point,Reagan became known -largely because...young drifter,John Hinckley. Ronald Wilson Reagan was born in a rented apartment...
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PA. REPUBLICAN PARTY: REMEMBERING PRESIDENT RONALD WILSON REAGAN
News Wire article from: Targeted News Service; 2/6/2007; 451 words
; ...system. "Serving with dignity and determination, Ronald Reagan's words transcended party affiliations as he expressed...admiration for the principles and values that President Ronald Wilson Reagan represents."Contact: Michael Barley, 717/234...
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Ronald Wilson Reagan--American.(The Insider)
Magazine article from: American Handgunner; 9/1/2004; ; 700+ words
; ...or met someone. But when asked if I'd ever met Ronald Wilson Reagan, I've always replied with these words: "I have...silver serving tray, a carafe and cups. It was Ronald Reagan. He brought us coffee. A moment later, I noticed...
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Ronald Wilson Reagan.(EDITORIALS)
Newspaper article from: The Washington Times; 6/6/2004; 700+ words
; ...summers at Lowell Park, young Dutch Reagan pulled 77 swimmers to safety...log. Fifty-five years later, Ronald Wilson Reagan, the man that Dutch grew into...the brink of decline. And then Ronald Reagan, who died yesterday at...
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The life of Ronald Wilson Reagan.(NATION)(RONALD REAGAN: 1911 - 2004)
Newspaper article from: The Washington Times; 6/7/2004; 700+ words
; ...itinerant shoe salesman John Edward "Jack" Reagan and his wife, Nelle Wilson Reagan. 1920 The Reagan family settles in Dixon, Ill., where his...individualistic, optimistic ethic in young Ronald that reflects Midwestern values of home...
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Blunt Floor Speech Honoring President Ronald Wilson Reagan
Newspaper article from: U.S. Newswire; 6/8/2004; 466 words
; ...room in the Whip's Office the Reagan Room for the brief time that I...the Soviet Union. "President Reagan said: 'We're a powerful force...large part because of President Ronald Wilson Reagan. "America's light shines a...
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Speaker Hastert's Statement on the House Floor Regarding the Late President Ronald Wilson Reagan
Newspaper article from: U.S. Newswire; 6/8/2004; 669 words
; ...House of Representatives regarding the late President Ronald Reagan: "Mr. Speaker, I rise today to honor the life and legacy of our nation's 40th President, Ronald Wilson Reagan. "He was born in the small town of Tampico, Illinois...
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Reagan, Ronald Wilson
Encyclopedia entry from: Gale Encyclopedia of U.S. Economic History
REAGAN, RONALD WILSON Folk wisdom holds that the burden of...true then no one knows that as well as Ronald Reagan. Born in Tampico, Illinois, on February 6, 1911, Ronald Wilson Reagan (1911 – ) grew...
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Ronald Wilson Reagan
Book article from: The Columbia Encyclopedia, Sixth Edition
Ronald Wilson Reagan , 1911-2004, 40th president of the...picture. Although never a major star, Reagan appeared in 50 films, including Knute...Bibliography: See his autobiography, Ronald Reagan: An American Life (1990, repr...
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Reagan, Ronald (Wilson)
Book article from: A Dictionary of World History
Reagan, Ronald (Wilson) (1911–2004) US Republican statesman, 40th President of the USA (1981–89). He was a Hollywood actor...
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Reagan, Ronald
Encyclopedia entry from: U*X*L Encyclopedia of World Biography
...1911, in Tampico, Illinois, Ronald Wilson Reagan was the second son of John Edward ("Jack") and Nelle Wilson Reagan. His parents were relatively poor...establish himself in business. When Ronald was nine the family moved to Dixon...
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Ronald W. Reagan
Encyclopedia entry from: Encyclopedia of World Biography
...1911, in Tampico, Illinois, Ronald Wilson Reagan was the second son of John Edward ("Jack") and Nelle Wilson Reagan. His parents were relatively poor...Monmouth, and then — when Ronald was nine — to Dixon...
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