Engineerin…

Editing

Volt

1
  • The edit can be undone. Please check the comparison below to verify that this is what you want to do, and then save the changes below to finish undoing the edit. If you are undoing an edit that is …
Latest revision Your text
Line 1: Line 1:
The '''volt''' (symbol: V) is the [[SI]] [[SI derived unit|derived unit]] of electric [[potential difference]]. The number of volts is a measure of the strength of an electrical source in the sense of how much power is produced for a given current level. It is named in honor of the Italian people, physicist, Alessandro Volta [http://en.wikipedia.org/wiki/Physicist] (1745–1827), who invented the voltaic pile [http://en.wikipedia.org/wiki/Voltaic_pile], the first chemical [[battery (electricity)|battery]].
+
The '''volt''' (symbol: V) is the [[SI]] [[SI derived unit|derived unit]] of electric [[potential difference]]. The number of volts is a measure of the strength of an electrical source in the sense of how much power is produced for a given current level. It is named in honor of the Italian people, physicist, Alessandro Volta[[http://en.wikipedia.org/wiki/Physicist]] (1745–1827), who invented the voltaic pile[[http://en.wikipedia.org/wiki/Voltaic_pile]], the first chemical [[battery (electricity)|battery]].
 
[[Image:180px-High_voltage_warning.svg.png|thumb|International [[High-voltage hazards|''danger high voltage'']] symbol.]]
 
[[Image:180px-High_voltage_warning.svg.png|thumb|International [[High-voltage hazards|''danger high voltage'']] symbol.]]
   
 
==Definition==
 
==Definition==
 
[[Image:180px-NISTvoltChip.jpg|thumb|Josephson junction array chip developed by [[NIST]] as a standard volt.]]
 
[[Image:180px-NISTvoltChip.jpg|thumb|Josephson junction array chip developed by [[NIST]] as a standard volt.]]
The volt is defined as the [[potential difference]] across a conductor when a [[Current (electricity)|current]] of one [[ampere]] dissipates one [[watt]] of [[power (physics)|power]]. Hence, it is the base SI representation [[metre|m]]<sup>2</sup> &middot; [[kilogram|kg]] &middot; [[second|s]]<sup>−3</sup> &middot; [[ampere|A]]<sup>−1</sup>, which can be equally represented as one [[joule]] of [[energy]] per [[coulomb]] of charge, J/C.
+
The volt is defined as the [[potential difference]] across a conductor when a [[Current (electricity)|current]] of one [[ampere]] dissipates one [[watt]] of [[power (physics)|power]]. Hence, it is the base SI representation [[metre|m]]<sup>2</sup> &middot; [[kilogram|kg]] &middot; [[second|s]]<sup>-3</sup> &middot; [[ampere|A]]<sup>-1</sup>, which can be equally represented as one [[joule]] of [[energy]] per [[coulomb]] of charge, J/C.
   
 
:1 V = 1 W/A = 1 m<sup>2</sup>•kg•s<sup>–3</sup>•A<sup>–1</sup>
 
:1 V = 1 W/A = 1 m<sup>2</sup>•kg•s<sup>–3</sup>•A<sup>–1</sup>
   
Since 1990 the volt is maintained internationally for practical measurement using the Josephson effect [http://en.wikipedia.org/wiki/Josephson_effect], where a conventional value is used for the Josephson constant [http://en.wikipedia.org/wiki/Josephson_constant], fixed by the 18th General Conference on Weights and Measures [http://en.wikipedia.org/wiki/General_Conference_on_Weights_and_Measures] as
+
Since 1990 the volt is maintained internationally for practical measurement using the Josephson effect[[http://en.wikipedia.org/wiki/Josephson_effect]], where a conventional value is used for the Josephson constant[[http://en.wikipedia.org/wiki/Josephson_constant]], fixed by the 18th General Conference on Weights and Measures[[http://en.wikipedia.org/wiki/General_Conference_on_Weights_and_Measures]] as
   
 
:'''K<sub>{J-90}</sub>''' = 0.4835979 GHz/µV.
 
:'''K<sub>{J-90}</sub>''' = 0.4835979 GHz/µV.
Line 112: Line 112:
 
== History of the volt ==
 
== History of the volt ==
   
In 1800, as the result of a professional disagreement over the galvanic response advocated by [[Luigi Galvani]], Alessandro Volta developed the so-called [[Voltaic pile]], a forerunner of the [[Battery (electricity)|battery]], which produced a steady electric [[current (electricity)|current]]. Volta had determined that the most effective pair of dissimilar metals to produce electricity was zinc [http://en.wikipedia.org/wiki/Zinc] and silver [http://en.wikipedia.org/wiki/Silver]. In the 1880s, the [[International Electrical Congress]], now the International Electrotechnical Commission (IEC)[http://en.wikipedia.org/wiki/International_Electrotechnical_Commission], approved the volt for electromotive force. The volt was defined as the potential difference across a conductor when a current of one [[ampere]] dissipates one [[watt]] of power.
+
In 1800, as the result of a professional disagreement over the galvanic response advocated by [[Luigi Galvani]], Alessandro Volta developed the so-called [[Voltaic pile]], a forerunner of the [[Battery (electricity)|battery]], which produced a steady electric [[current (electricity)|current]]. Volta had determined that the most effective pair of dissimilar metals to produce electricity was zinc[[http://en.wikipedia.org/wiki/Zinc]] and silver[[http://en.wikipedia.org/wiki/Silver]]. In the 1880s, the [[International Electrical Congress]], now the International Electrotechnical Commission (IEC)[[http://en.wikipedia.org/wiki/International_Electrotechnical_Commission]], approved the volt for electromotive force. The volt was defined as the potential difference across a conductor when a current of one [[ampere]] dissipates one [[watt]] of power.
   
Prior to the development of the Josephson junction voltage standard, the volt was maintained in national laboratories using specially constructed batteries called '''standard cells'''. The United States used a design called the Weston cell [http://en.wikipedia.org/wiki/Weston_cell] from 1905 to 1972.
+
Prior to the development of the Josephson junction voltage standard, the volt was maintained in national laboratories using specially constructed batteries called '''standard cells'''. The United States used a design called the Weston cell[[http://en.wikipedia.org/wiki/Weston_cell]] from 1905 to 1972.
   
 
==See also==
 
==See also==
  Loading editor
Below are some commonly used wiki markup codes. Simply click on what you want to use and it will appear in the edit box above.

View this template