Volt
From Biocrawler, the free encyclopedia.
The volt is the SI derived unit for electric potential and voltage (derived from the ampere and watt). It is named in honor of Alessandro Volta, who, in 1800, invented the voltaic pile, the first chemical battery.
The volt is defined as the potential difference across a conductor when a current of one ampere dissipates one watt of power. Hence, it is has the base SI representation m2 · kg · s-3 · A-1, which can be equally represented as one joule of energy per coulomb of charge, J/C. In essence, the volt measures how much kinetic energy each electron, measured in coulombs, carries, this aside from charge. Thus the volt, one factor of energy is multiplied by the current flow, the ampere, to yield the total electrical power in the current, in Watts.
Since 1990 the volt is maintained internationally using the Josephson effect, where a conventional value is used for the Josephson constant, fixed by the 18th CGPM as
K{J-90} = 0.4835979 GHz/猩.
SI electricity units
| SI electromagnetism units edit (http://www.biocrawler.com/w/index.php?title=Template:SI_electromagnetism_units&action=edit) | |||
|---|---|---|---|
| Name | Symbol | Dimensions | Quantity |
| ampere (SI base unit) | A | A | Current |
| coulomb | C | A新 | Electric charge, Quantity of electricity |
| volt | V | J/C = kg搶2新−3嫂−1 | Potential difference |
| ohm | Ω | V/A = kg搶2新−3嫂−2 | Resistance, Impedance, Reactance |
| ohm metre | Ω搶 | kg搶3新−3嫂−2 | Resistivity |
| watt | W | V嫂 = kg搶2新−3 | Electrical power |
| farad | F | C/V = kg−1搶−2嫂2新4 | Capacitance |
| farad per metre | F/m | kg−1搶−3嫂2新4 | Permittivity |
| reciprocal farad | F−1 | kg1搶2嫂−2新−4 | Elastance |
| siemens | S | Ω−1 = kg−1搶−2新3嫂2 | Conductance, Admittance, Susceptance |
| siemens per metre | S/m | kg−1搶−3新3嫂2 | Conductivity |
| weber | Wb | V新 = kg搶2新−2嫂−1 | Magnetic flux |
| tesla | T | Wb/m2 = kg新−2嫂−1 | Magnetic flux density |
| ampere per metre | A/m | m−1嫂 | magnetic induction |
| ampere-turns per weber | A/Wb | kg−1搶−2新2嫂2 | Reluctance |
| henry | H | Wb/A = V新/A = kg搶2新−2嫂−2 | Inductance |
| henry per metre | H/m | kg搶新−2嫂−2 | Permeability |
| (dimensionless) | χ | - | Magnetic susceptibility |
See also
cs:Volt da:Voltes:voltio et:Volt fi:voltti fr:Volt he:וולט it:Volt ja:ボルト (単位) nl:Volt no:Volt pl:Wolt pt:Volt sl:volt sv:Volt ru:Вольт sr:Волт zh:伏特
