|
Search over 100 encyclopedias and dictionaries: |
Research categories | Follow us on Twitter |
Research categories
View all topics in the newsView all reference sources at Encyclopedia.com |
|||
quark
quark A fundamental particle, of which hadrons are believed to be composed. Quarks have charges that are either +⅔ or −⅓ of the electron's charge, and combine to make elementary particles. Baryons consist of three quarks, and mesons of two. For example, a proton consists of quarks with charges +⅔+⅔−⅓= 1 and a neutron consists of three with charges +⅔−⅔−⅓ = 0. Eighteen different quarks with various properties are thought to exist, with a corresponding number of antiquarks. An isolated quark has never been observed; quarks appear to exist only in combination as baryons or mesons.
|
|
|
Cite this article
"quark." A Dictionary of Astronomy. 1997. Encyclopedia.com. 28 May. 2012 <http://www.encyclopedia.com>. "quark." A Dictionary of Astronomy. 1997. Encyclopedia.com. (May 28, 2012). http://www.encyclopedia.com/doc/1O80-quark.html "quark." A Dictionary of Astronomy. 1997. Retrieved May 28, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O80-quark.html |
|
quark
quark Any one of six particles (although there is increasing evidence of another two) and their antiparticles (antiquarks) that are the constituents of the hadron group of elementary particles. They occur in one of six ‘flavours’: up, down, top, bottom, charmed, and strange. Antiquarks have similar flavours but their charge is opposite that of their corresponding quark. Quarks always exist in combination; free quarks cannot exist. A baryon, such as a proton or neutron, consists of three.
|
|
|
Cite this article
"quark." World Encyclopedia. 2005. Encyclopedia.com. 28 May. 2012 <http://www.encyclopedia.com>. "quark." World Encyclopedia. 2005. Encyclopedia.com. (May 28, 2012). http://www.encyclopedia.com/doc/1O142-quark.html "quark." World Encyclopedia. 2005. Retrieved May 28, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O142-quark.html |
|
quark
quark in physics, any of a number of subatomic particles carrying a fractional electric charge, postulated as building blocks of the hadrons. Quarks have not been directly observed but theoretical predictions based on their existence have been confirmed experimentally. The name (originally quork) was invented in the 1960s by Murray Gell-Mann; it was changed by association with the line ‘Three quarks for Muster Mark’ in Joyce's Finnegans Wake (1939).
|
|
|
Cite this article
ELIZABETH KNOWLES. "quark." The Oxford Dictionary of Phrase and Fable. 2006. Encyclopedia.com. 28 May. 2012 <http://www.encyclopedia.com>. ELIZABETH KNOWLES. "quark." The Oxford Dictionary of Phrase and Fable. 2006. Encyclopedia.com. (May 28, 2012). http://www.encyclopedia.com/doc/1O214-quark.html ELIZABETH KNOWLES. "quark." The Oxford Dictionary of Phrase and Fable. 2006. Retrieved May 28, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O214-quark.html |
|
quark
quark1 / kwärk/ • n. Physics any of a number of subatomic particles carrying a fractional electric charge, postulated as building blocks of the hadrons. Quarks have not been directly observed, but theoretical predictions based on their existence have been confirmed experimentally. quark2 • n. a type of low-fat curd cheese. |
|
|
Cite this article
"quark." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. 28 May. 2012 <http://www.encyclopedia.com>. "quark." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. (May 28, 2012). http://www.encyclopedia.com/doc/1O999-quark.html "quark." The Oxford Pocket Dictionary of Current English. 2009. Retrieved May 28, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O999-quark.html |
|
quark
quark (quarg) Originally German; very low‐fat cheese made from skim milk; contains 80% water; a 100‐g portion is a good source of protein and vitamin B12, a source of vitamin B2, with only a trace of fat, contains 40 mg of sodium and 90 mg of calcium and supplies 80 kcal (325 kJ).
|
|
|
Cite this article
DAVID A. BENDER. "quark." A Dictionary of Food and Nutrition. 2005. Encyclopedia.com. 28 May. 2012 <http://www.encyclopedia.com>. DAVID A. BENDER. "quark." A Dictionary of Food and Nutrition. 2005. Encyclopedia.com. (May 28, 2012). http://www.encyclopedia.com/doc/1O39-quark.html DAVID A. BENDER. "quark." A Dictionary of Food and Nutrition. 2005. Retrieved May 28, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O39-quark.html |
|
quark
quark : see elementary particles . |
|
|
Cite this article
"quark." The Columbia Encyclopedia, 6th ed.. 2011. Encyclopedia.com. 28 May. 2012 <http://www.encyclopedia.com>. "quark." The Columbia Encyclopedia, 6th ed.. 2011. Encyclopedia.com. (May 28, 2012). http://www.encyclopedia.com/doc/1E1-X-quark.html "quark." The Columbia Encyclopedia, 6th ed.. 2011. Retrieved May 28, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1E1-X-quark.html |
|
quark
quark •arc, ark, Bach, bark, barque, Braque, Clark, clerk, dark, embark, hark, impark, Iraq, Ladakh, Lamarck, lark, macaque, marc, mark, marque, narc, nark, Newark, park, quark, sark, shark, snark, spark, stark, Vlach
•matriarch, patriarch
•tanbark • ringbark • stringy-bark
•Offenbach • ironbark • oligarch
•salesclerk • titlark • skylark
•meadowlark • woodlark • mudlark
•landmark • checkmark • Denmark
•benchmark • waymark • trademark
•seamark • Bismarck • telemark
•tidemark • Kitemark • pockmark
•Ostmark • hallmark • Goldmark
•Deutschmark • bookmark • footmark
•earmark • watermark • birthmark
•anarch • car park • skatepark
•ballpark
•Petrarch, tetrarch
•hierarch, squirearch
•exarch • Pesach • loan shark
•Plutarch • aardvark
|
|
|
Cite this article
"quark." Oxford Dictionary of Rhymes. 2007. Encyclopedia.com. 28 May. 2012 <http://www.encyclopedia.com>. "quark." Oxford Dictionary of Rhymes. 2007. Encyclopedia.com. (May 28, 2012). http://www.encyclopedia.com/doc/1O233-quark.html "quark." Oxford Dictionary of Rhymes. 2007. Retrieved May 28, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O233-quark.html |
|
|
Search over 100 encyclopedias and dictionaries:
HighBeam™ Research, Inc. © Copyright 2012. All rights reserved.
The Encyclopedia.com advertising network includes:
