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rheostat
rheostat , device whose resistance to electric current depends on the position of some mechanical element or control in the device. Typically a rheostat consists of a resistance element equipped with two contacts, or terminals, by which it is attached to a circuit: a fixed contact at one end and a sliding contact that can be moved along the resistance element. Electric current enters and leaves the resistance element through the contacts. By moving the sliding contact toward or away from the fixed contact, the length of the resistance element through which the current travels can be decreased or increased. In this way the current through the circuit can be increased or decreased. Rheostats are widely used for such purposes as controlling the speed of electric motors and dimming electric lights, but they have been replaced in many applications by systems based on semiconductor devices that waste far less power. See potentiometer . |
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"rheostat." The Columbia Encyclopedia, 6th ed.. 2008. Encyclopedia.com. 11 Feb. 2012 <http://www.encyclopedia.com>. "rheostat." The Columbia Encyclopedia, 6th ed.. 2008. Encyclopedia.com. (February 11, 2012). http://www.encyclopedia.com/doc/1E1-rheostat.html "rheostat." The Columbia Encyclopedia, 6th ed.. 2008. Retrieved February 11, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1E1-rheostat.html |
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rheostat
rhe·o·stat / ˈrēəˌstat/ • n. an electrical instrument used to control a current by varying the resistance. DERIVATIVES: rhe·o·stat·ic / ˌrēəˈstatik/ adj. |
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Cite this article
"rheostat." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. 11 Feb. 2012 <http://www.encyclopedia.com>. "rheostat." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. (February 11, 2012). http://www.encyclopedia.com/doc/1O999-rheostat.html "rheostat." The Oxford Pocket Dictionary of Current English. 2009. Retrieved February 11, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O999-rheostat.html |
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rheostat
rheostat Variable resistor for regulating an electric current. The resistance element may be a metal wire, carbon or a conducting liquid. Rheostats are used to adjust generators, to dim lights and to control the speed of electric motors.
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"rheostat." World Encyclopedia. 2005. Encyclopedia.com. 11 Feb. 2012 <http://www.encyclopedia.com>. "rheostat." World Encyclopedia. 2005. Encyclopedia.com. (February 11, 2012). http://www.encyclopedia.com/doc/1O142-rheostat.html "rheostat." World Encyclopedia. 2005. Retrieved February 11, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O142-rheostat.html |
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rheostat
rheostat •Eurocrat • ziggurat • muskrat
•theocrat • jurat • Ballarat • democrat
•technocrat • bureaucrat • aristocrat
•autocrat • plutocrat • babysat
•Comsat • Randstad • Darmstadt
•diktat • habitat • Eisenstadt
•Kronstadt • cryostat • aerostat
•aegrotat • rheostat • haemostat
•thermostat • photostat
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Cite this article
"rheostat." Oxford Dictionary of Rhymes. 2007. Encyclopedia.com. 11 Feb. 2012 <http://www.encyclopedia.com>. "rheostat." Oxford Dictionary of Rhymes. 2007. Encyclopedia.com. (February 11, 2012). http://www.encyclopedia.com/doc/1O233-rheostat.html "rheostat." Oxford Dictionary of Rhymes. 2007. Retrieved February 11, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O233-rheostat.html |
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