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Henry (inductance)

The henry (symbol H) is the SI unit of inductance. If the rate of change of current in a circuit is one ampere per second and the resulting electromotive force is one volt, then the inductance of the circuit is one henry.

The henry has dimensions VA-1s = m²kgs-2A-2 in SI units.

The unit is named after the American scientist Joseph Henry.

SI electricity units

SI electromagnetism units

Name Symbol Dimensions Quantity
ampere (SI base unit) A C / s Current
coulomb C A · s Electric charge, Quantity of electricity
volt V J / C = kg m2 / (s2 C) Potential difference
ohm Ω V / A = kg m2 / (C2) Resistance, Impedance, Reactance
ohm &middot metre Ω &middot m kg m3 / (C2) Resistivity
farad F C / V = C2 s / (kg m2) Capacitance
farad per metre F / m C2 s / (kg m3) Permittivity
reciprocal farad F−1 kg m2 / (C2 s) Elastance
siemens S Ω−1 = C2 / (kg m2) Conductance, Admittance, Susceptance
siemens per metre S / m C2 / (kg m3) Conductivity
weber Wb V &middot s = kg m2 / (C s) Magnetic flux
tesla T Wb / m2 = kg / (C s) Magnetic flux density
ampere / metre A / m C / (s m) magnetic induction
ampere-turns / weber A / Wb C2 / (kg m2) Reluctance
henry H V &middot s / A = kg m2 s / (C2) Inductance
henry per metre H / m kg m s / (C2) Permeability
(dimensionless) - - Magnetic susceptibility

Last updated: 02-06-2005 17:38:55
Last updated: 05-03-2005 17:50:55