View source for Statvolt

{{Short description|A CGS-ESU and gaussian unit of voltage}}
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Note: the reason why [[Template:Infobox unit|Infobox unit]] is not used is that conversions between CGS-ESU, CGS-EMU, and SI units for electromagnetic quantities have to use the expression 'corresponds to' rather than 'equals', as in '1 abCoulomb corresponds to 2.99 × 10^10 statCoulombs'. The symbol for that is '≘' or '≙'. See e.g. https://arxiv.org/abs/1506.01951, pp. 57–59. 
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{{Infobox
 | above   = statvolt
 |  label2 = [[System of measurement|Unit system]]     | data2 = [[Centimetre–gram–second_system_of_units#Electrostatic_units_(ESU)|CGS-ESU]] and [[Gaussian units|CGS-Gaussian]]
 |  label3 = Unit of     | data3 = [[electric potential]], [[electric potential difference]] ([[voltage]]), and [[electromotive force]]
 |  label4 = Symbol      | data4 = statV
 |  label5 = Named after | data5 = [[Alessandro Volta]]
 |  label6 = In CGS base units      | data6 = g{{sup|1/2}}·cm{{sup|1/2}}/s&nbsp;{{refn|name="Gyllenbok 2018"|
    {{cite book
      |last1=Gyllenbok |first1=Jan
      |title=Encyclopaedia of Historical Metrology, Weights, and Measures: Volume 1
      |date=2018
      |publisher=Birkhäuser |isbn=978-3-319-57598-8 |language=en
    }}}}<sup>:[https://books.google.com/books?id=XnRVDwAAQBAJ&dq=%22Encyclopaedia%20of%20Historical%20Metrology%2C%20Weights%2C%20and%20Measures%22%20vol%201&pg=PA26 26]</sup>
 | header7 =Conversions
 | data8 =  <tr class="nowrap"><td>{{val|1|u=statV}} ''in ...''</td><td>''... corresponds to ...''</td></tr>
 | label9 = [[SI]] | data9 = {{math|''c''}}{{sub|cgs}}&nbsp;{{val|e=-8|ul=volt}}{{br}}= {{val|299.792458|u=volt}}{{efn|name="cCGC"|The dimensionless constant {{math|''c''}}{{sub|cgs}} {{=}} {{val|2.99792458e10}} is numerically equal to the magnitude of the [[speed of light]] when the latter is expressed in {{val|u=cm/s}}.}}
 | label10 = [[Centimetre–gram–second_system_of_units#Electrostatic_units_(ESU)|CGS-EMU]] 
 | data10 = {{math|''c''}}{{sub|cgs}}&nbsp;[[abvolt]]
}}
The '''statvolt''' is a unit of [[voltage]] and [[electrical potential]] used in the [[Centimetre–gram–second_system_of_units#Electrostatic_units_(ESU)|CGS-ESU]] and [[Gaussian units|gaussian]] systems of units. In terms of its relation to the [[SI]] units, one statvolt corresponds to {{math|''c''}}{{sub|cgs}}&nbsp;{{val|e=-8|ul=volt}},{{efn|name="cCGC"}} i.e. to 299.792458&nbsp;[[volt]]s.{{refn|name="Purcell"|{{cite book|last=Purcell|first=Edward|title=Electricity and Magnetism|url=https://archive.org/details/electricitymagne00purc_621|url-access=limited|year=2011|publisher=Cambridge University Press|location=Cambridge|isbn=9781107013605|pages=[https://archive.org/details/electricitymagne00purc_621/page/n493 474]–475|edition=Second}}}}{{efn|As of the [[2019 revision of the SI]], this correspondence is not longer exact.}}

The statvolt is also defined in the [[CGS]] system as 1&nbsp;[[erg]] per [[statcoulomb]].{{refn|name="Purcell"}}
It is a useful unit for [[electromagnetism]] because, in vacuum, an [[electric field]] of one statvolt per centimetre has the same energy density as a [[magnetic field]] of one [[Gauss (unit)|gauss]].  Likewise, a plane wave propagating in vacuum has perpendicular electric and magnetic fields such that for every gauss of magnetic field intensity there is one statvolt/cm of electric field intensity.{{refn|name="Purcell"}}

In the CGS-EMU system, the unit of voltage is the [[abvolt]].

==Additional Information==
The statvolt is a fundamental unit of electric potential in the [[centimetre-gram-second]] electrostatic unit (CGS-ESU) and Gaussian unit systems. It is defined as the potential difference between two points that imparts one erg of energy per statcoulomb of charge. This unit's relevance stems from its convenient relationship to electromagnetic quantities in [[vacuum]], where an [[electric field]] of one statvolt per centimetre corresponds energetically to a [[magnetic field]] of one gauss.

In practical terms, one statvolt is equivalent to approximately 299.792458 [[Volt|volts]] in the International System of Units (SI), which makes it significantly larger than the standard volt. This conversion factor arises from the speed of light, c, linking electromagnetic units in the CGS system to those in SI.

Unlike the statvolt, the CGS electromagnetic unit (CGS-EMU) system uses the abvolt as its voltage unit, which differs significantly in [[Magnitude_(mathematics)|magnitude]] and [[definition]].<ref>https://www.mathconverse.com/en/Definitions/Units/Statvolt/</ref><ref>https://www.knowledgedoor.com/2/units_and_constants_handbook/statvolt.html</ref>

== Notes ==
{{notelist}}

== References ==
{{reflist}}

{{CGS units}}

[[Category:Units of electrical potential]]
[[Category:Centimetre–gram–second system of units]]