See also: List of concrete quantities and List of electromagnetism equations
Electromagnetic units are allotment of a arrangement of electrical units based primarily aloft the alluring backdrop of electric currents, the axiological SI assemblage getting the ampere. The units are:
ampere (electric current)
coulomb (electric charge)
farad (capacitance)
henry (inductance)
ohm (resistance)
tesla (magnetic alteration density)
volt (electric potential)
watt (power)
weber (magnetic flux)
In the electromagnetic cgs system, electric accepted is a axiological abundance authentic via AmpГЁre's law and takes the permeability as a dimensionless abundance (relative permeability) whose amount in a exhaustion is unity. As a consequence, the aboveboard of the acceleration of ablaze appears absolutely in some of the equations commutual quantities in this system.
SI electromagnetism units v t e
Symbol[3] Name of Quantity Derived Units Unit Base Units
I electric current ampere (SI abject unit) A A (= W/V = C/s)
Q electric charge coulomb C Aв‹…s
U, О”V, О”П†; E potential difference; electromotive force volt V kgв‹…m2в‹…sв€’3в‹…Aв€’1 (= J/C)
R; Z; X electric resistance; impedance; reactance ohm О© kgв‹…m2в‹…sв€’3в‹…Aв€’2 (= V/A)
ПЃ resistivity ohm metre О©в‹…m kgв‹…m3в‹…sв€’3в‹…Aв€’2
P electric power watt W kgв‹…m2в‹…sв€’3 (= Vв‹…A)
C capacitance farad F kgв€’1в‹…mв€’2в‹…s4в‹…A2 (= C/V)
E electric acreage strength volt per metre V/m kgв‹…mв‹…sв€’3в‹…Aв€’1 (= N/C)
D electric displacement field coulomb per aboveboard metre C/m2 Aв‹…sв‹…mв€’2
Оµ permittivity farad per metre F/m kgв€’1в‹…mв€’3в‹…s4в‹…A2
χe electric susceptibility (dimensionless) – –
G; Y; B conductance; admittance; susceptance siemens S kgв€’1в‹…mв€’2в‹…s3в‹…A2 (= О©в€’1)
Оє, Оі, Пѓ conductivity siemens per metre S/m kgв€’1в‹…mв€’3в‹…s3в‹…A2
B magnetic alteration density, alluring induction tesla T kgв‹…sв€’2в‹…Aв€’1 (= Wb/m2 = Nв‹…Aв€’1в‹…mв€’1)
\Phi magnetic flux weber Wb kgв‹…m2в‹…sв€’2в‹…Aв€’1 (= Vв‹…s)
H magnetic acreage strength ampere per metre A/m Aв‹…mв€’1
L, M inductance henry H kgв‹…m2в‹…sв€’2в‹…Aв€’2 (= Wb/A = Vв‹…s/A)
Ој permeability henry per metre H/m kgв‹…mв‹…sв€’2в‹…Aв€’2
χ magnetic susceptibility (dimensionless) – –
Formulas for concrete laws of electromagnetism (such as Maxwell's equations) charge to be adapted depending on what arrangement of units one uses. This is because there is no one-to-one accord amid electromagnetic units in SI and those in CGS, as is the case for automated units. Furthermore, aural CGS, there are several believable choices of electromagnetic units, arch to altered assemblage "sub-systems", including Gaussian, "ESU", "EMU", and Heaviside–Lorentz. Among these choices, Gaussian units are the a lot of accepted today, and in actuality the byword "CGS units" is generally acclimated to accredit accurately to CGS-Gaussian units.
Electromagnetic units are allotment of a arrangement of electrical units based primarily aloft the alluring backdrop of electric currents, the axiological SI assemblage getting the ampere. The units are:
ampere (electric current)
coulomb (electric charge)
farad (capacitance)
henry (inductance)
ohm (resistance)
tesla (magnetic alteration density)
volt (electric potential)
watt (power)
weber (magnetic flux)
In the electromagnetic cgs system, electric accepted is a axiological abundance authentic via AmpГЁre's law and takes the permeability as a dimensionless abundance (relative permeability) whose amount in a exhaustion is unity. As a consequence, the aboveboard of the acceleration of ablaze appears absolutely in some of the equations commutual quantities in this system.
SI electromagnetism units v t e
Symbol[3] Name of Quantity Derived Units Unit Base Units
I electric current ampere (SI abject unit) A A (= W/V = C/s)
Q electric charge coulomb C Aв‹…s
U, О”V, О”П†; E potential difference; electromotive force volt V kgв‹…m2в‹…sв€’3в‹…Aв€’1 (= J/C)
R; Z; X electric resistance; impedance; reactance ohm О© kgв‹…m2в‹…sв€’3в‹…Aв€’2 (= V/A)
ПЃ resistivity ohm metre О©в‹…m kgв‹…m3в‹…sв€’3в‹…Aв€’2
P electric power watt W kgв‹…m2в‹…sв€’3 (= Vв‹…A)
C capacitance farad F kgв€’1в‹…mв€’2в‹…s4в‹…A2 (= C/V)
E electric acreage strength volt per metre V/m kgв‹…mв‹…sв€’3в‹…Aв€’1 (= N/C)
D electric displacement field coulomb per aboveboard metre C/m2 Aв‹…sв‹…mв€’2
Оµ permittivity farad per metre F/m kgв€’1в‹…mв€’3в‹…s4в‹…A2
χe electric susceptibility (dimensionless) – –
G; Y; B conductance; admittance; susceptance siemens S kgв€’1в‹…mв€’2в‹…s3в‹…A2 (= О©в€’1)
Оє, Оі, Пѓ conductivity siemens per metre S/m kgв€’1в‹…mв€’3в‹…s3в‹…A2
B magnetic alteration density, alluring induction tesla T kgв‹…sв€’2в‹…Aв€’1 (= Wb/m2 = Nв‹…Aв€’1в‹…mв€’1)
\Phi magnetic flux weber Wb kgв‹…m2в‹…sв€’2в‹…Aв€’1 (= Vв‹…s)
H magnetic acreage strength ampere per metre A/m Aв‹…mв€’1
L, M inductance henry H kgв‹…m2в‹…sв€’2в‹…Aв€’2 (= Wb/A = Vв‹…s/A)
Ој permeability henry per metre H/m kgв‹…mв‹…sв€’2в‹…Aв€’2
χ magnetic susceptibility (dimensionless) – –
Formulas for concrete laws of electromagnetism (such as Maxwell's equations) charge to be adapted depending on what arrangement of units one uses. This is because there is no one-to-one accord amid electromagnetic units in SI and those in CGS, as is the case for automated units. Furthermore, aural CGS, there are several believable choices of electromagnetic units, arch to altered assemblage "sub-systems", including Gaussian, "ESU", "EMU", and Heaviside–Lorentz. Among these choices, Gaussian units are the a lot of accepted today, and in actuality the byword "CGS units" is generally acclimated to accredit accurately to CGS-Gaussian units.
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