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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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	Murder investigation after body found in field near Thame. Newspaper article from: Thame Gazette (Thame, England); 7/16/2007; 262 words ; ...after a badly burnt woman's body was found in a field near Thame. At a press conference...more details regarding the body found near Milton Common...had been discovered in a field off Rycote Lane in Milton Common. The body had been badly burnt. He... Read more
	2: The development of the field of entrepreneurship.(Entrepreneurship Research: Past Perspectives and Future Prospects) Magazine article from: Foundations and Trends in Entrepreneurship; 12/1/2006; ; 700+ words ; ...the young faculties devoting their full attention to the field. Historically, part-time faculties have done much of the...are unlikely to contribute to the research-base of the field. In addition, some of the full-time faculties who have...careers. Furthermore, some of the faculties attracted to the ... Read more
	Identifying and Using Your Field's Body of Knowledge. (Briefly). Magazine article from: Association Management; 9/1/2002; 71 words ; Identifying and Using Your Field's Body of Knowledge, by Mickie S. Rops, CAE, is now available from the ASAE Bookstore. The book includes case studies and other tools... Read more
	Field not out to grass just yet. Newspaper article from: Evening Courier (Halifax, England); 4/5/2008; 452 words ; ...the world and that is what has kept me going. That said, Field went perilously close to never even getting his hands on...but I always thought I was too small to play rugby, said Field. I was always a footballer until Geoff Cooke got hold of...to Hunslet and signed up for the under 17s. After that, Field ... Read more
	State crime lab studies body parts from field.(General News)(Testing: Identification will be difficult because farm equipment cut up and scattered the human remains.) Newspaper article from: The Register-Guard (Eugene, OR); 9/7/2002; 384 words ; ...the mystery of how the body ended up in the field was no closer to being...question. It appears the body had been in the field since early spring, Mueller...searched. A number of the body parts recovered from the field have been sent to the Oregon... Read more
	UO receivers coach slowly making his way back.(Sports)(Robin Pflugrad returns to the field after undergoing neck vertebrae surgery) Newspaper article from: The Register-Guard (Eugene, OR); 4/28/2006; 696 words ; ...eases back into being on the field with his receivers. He actually...along. `When they start taking body parts out and putting in other...animated, he is back on the field. In his absence, head coach...the receivers on the practice field. Between the absences for academics...for conflicts with ... Read more
	Words from the field. Magazine article from: Policy & Practice; 6/1/2008; ; 700+ words ; ...have a visual aid as to how often I was going out into the field? Was it so I could be found in case another family was...and training director. But what has not changed in the field of child welfare, and social work in general, is the importance...risks social workers face every time they head into the ... Read more
	A bounded Field: situating Victorian poetry in the literary landscape.(Victorian woman poet, Michael Field) Magazine article from: Victorian Poetry; 12/22/2003; ; 700+ words ; ...in Leighton's book. And yet as much as any poet, Michael Field demands to be read against a large and varied artistic...books of lyrics to be published under the name Michael Field (4) both parade their participation in age-old traditions...poetic. The next step in the critical history of Michael Field ... Read more
	Man found dead in field. Newspaper article from: Sunderland Echo (Pennywell, England); 11/20/2007; 46 words ; The body of a man was found in a field behind the Red Lion pub in Plawsworth on Saturday afternoon. He has been named as Arthur Phillips, 31, of Gainford, Chester-le... Read more
	Woman, 87, died alone in field. Newspaper article from: Northampton Chronicle and Echo (Northampton, England); 4/17/2008; 294 words ; A former civil servant found dead in a field in Northamptonshire after being missing for five days had...Daventry, only a month earlier. Police found Mrs Powell's body in a field off the A361 on November 22. In a statement read at her inquest...rain on November 18, four days before police recovered her ... Read more

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