Electric current[edit]

Electric current

Relation to SI Name of unit Symbol Definition units

≡ The constant current needed to produce a force of 2 ×10−7 newton per metre between two straight ampere (SI base A parallel conductors of infinite = 1 A = 1 C/s unit) length and negligible circular cross-section placed one metre apart in a vacuum.[8] electromagnetic unit; abampere abamp ≡ 10 A = 10 A (cgs unit) esu per second; statampere (cgs esu/s ≡ (0.1 A·m/s) / c ≈3.335641×10−10 A unit) Electric charge[edit]

Electric charge

Relation to SI Name of unit Symbol Definition units abcoulomb; abC; electromagnetic unit (cgs ≡ 10 C = 10 C emu unit)

≈1.602 176 atomic unit of charge au ≡ e 462×10−19C ≡ The amount of electricity

coulomb C carried in one second of = 1 C = 1 A·s time by one ampere of current.[25] ≈ 96 faraday F ≡ 1 mol × N ·e A 485.3383 C milliampere hour mA·h ≡ 0.001 A × 1 h = 3.6 C statcoulomb; franklin; statC; Fr; ≈ 3.335 ≡ (0.1 A·m) / c electrostatic unit (cgs unit) esu 641×10−10 C Electric dipole[edit]

Electric dipole

Name of unit Symbol Definition Relation to SI units atomic unit of electric dipole ≈ 8.478 352

ea moment 0 81×10−30 C·m[29] coulomb meter C·m = 1 C · 1 m

= −30 [30] debye D = 3.33564095×10 C·m 10−10 esu·Å Electromotive force, electric potential difference[edit]

Voltage, electromotive force

Name of Relation to SI Symbol Definition unit units abvolt(cgs abV ≡ 1×10−8 V = 1×10−8 V unit) statvolt(cgs = 299.792 statV ≡ c· (1 μJ/A·m) unit) 458 V The difference in electric potential across two points along a conducting wire carrying = 1 V = 1 W/A volt (SI unit) V one ampere of constant current when the =1 kg·m2/(A·s3) power dissipated between the points equals one watt.[25] Electrical resistance[edit]

Electrical resistance

Name of Relation to SI Symbol Definition unit units

The resistance between two points in a ohm (SI conductor when one volt of electric potential = 1 Ω = 1 V/A Ω unit) difference, applied to these points, produces =1 kg·m2/(A2·s3) one ampere of current in the conductor.[25]

Capacitance[edit]

Capacitor's ability to store charge

Name of Relation to SI Symbol Definition unit units

The capacitance between two parallel plates farad (SI that results in one volt of potential difference = 1 F = 1 C/V =1 F unit) when charged by one coulomb of A2·s4/(kg·m2) electricity.[25]

Magnetic flux[edit]

magnetic flux

Relation to SI Name of unit Symbol Definition units maxwell(CGS Mx ≡ 10−8 Wb[31] = 1×10−8 Wb unit)

Magnetic flux which, linking a circuit of = 1 Wb = 1 V·s weber (SI unit) Wb one turn, would produce in it an =1 kg·m2/(A·s2) electromotive force of 1 volt if it were reduced to zero at a uniform rate in 1 second.[25] Magnetic flux density[edit]

What physicists call Magnetic field is called Magnetic flux density by electrical engineers and magnetic induction by applied mathematicians and electrical engineers.

Name of unit Symbol Definition Relation to SI units gauss (CGS unit) G ≡ Mx/cm2 = 10−4 T = 1×10−4 T [32]

= 1 T = 1 Wb/m2 = 1 tesla (SI unit) T ≡ Wb/m2 kg/(A·s2) Inductance[edit]

Inductance

Name of Relation to SI Symbol Definition unit units

The inductance of a closed circuit that henry(SI produces one volt of electromotive force when = 1 H = 1 Wb/A H unit) the current in the circuit varies at a uniform =1 kg·m2/(A·s)2 rate of one ampere per second.[25]