# Henry (unit)

henryhenriesHExahenryGigahenryMegahenryMillihenryPicohenryZettahenryAh
The henry (symbol: H) is the SI derived unit of electrical inductance.wikipedia
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### Inductance

mutual inductanceinductivemutual induction
The henry (symbol: H) is the SI derived unit of electrical inductance. The inductance of an electric circuit is one henry when an electric current that is changing at one ampere per second results in an electromotive force of one volt across the inductor: Formulas can be used to calculate the inductance of many common arrangements of conductors, such as parallel wires, or a solenoid.
In the SI system, the unit of inductance is the henry (H), which is the amount of inductance that causes a voltage of one volt, when the current is changing at a rate of one ampere per second.

### Joseph Henry

Henry, JosephHenryJoseph Henry Papers Project
If a current of 1 ampere flowing through the coil produces flux linkage of 1 weber turn, the coil has a self inductance of 1 henry.‌ The unit is named after Joseph Henry (1797–1878), the American scientist who discovered electromagnetic induction independently of and at about the same time as Michael Faraday (1791–1867) in England.
The SI unit of inductance, the Henry, is named in his honor.

### SI derived unit

derived unitderived unitsJ/kg
The henry (symbol: H) is the SI derived unit of electrical inductance. The henry is a derived unit based on four of the seven base units of the International System of Units: kilogram (kg), metre (m), second (s), and ampere (A).

### Weber (unit)

weberWbwebers
If a current of 1 ampere flowing through the coil produces flux linkage of 1 weber turn, the coil has a self inductance of 1 henry.‌ The unit is named after Joseph Henry (1797–1878), the American scientist who discovered electromagnetic induction independently of and at about the same time as Michael Faraday (1791–1867) in England. :in which the following additional derived units occur: coulomb (C), farad (F), joule (J), weber (Wb), tesla (T), volt (V), hertz (Hz), and ohm .
H = henry,

### International System of Units

SISI unitsSI unit
The henry is a derived unit based on four of the seven base units of the International System of Units: kilogram (kg), metre (m), second (s), and ampere (A).

### Kilogram

kgmgmilligram
The henry is a derived unit based on four of the seven base units of the International System of Units: kilogram (kg), metre (m), second (s), and ampere (A).
Three other base units (cd, A, mol) and 17 derived units (N, Pa, J, W, C, V, F, Ω, S, Wb, T, H, kat, Gy, Sv, lm, lx) in the SI system were defined in relation to the kilogram, and thus its stability was important.

### Joule

JkJMJ
:in which the following additional derived units occur: coulomb (C), farad (F), joule (J), weber (Wb), tesla (T), volt (V), hertz (Hz), and ohm .
At the second International Electrical Congress, on 31 August 1889, the joule was officially adopted alongside the watt and the quadrant (later renamed to henry).

### Permeability (electromagnetism)

permeabilitymagnetic permeabilityrelative permeability
The inductance of a coil depends on its size, the number of turns, and the permeability of the material within and surrounding the coil.
In SI units, permeability is measured in henries per meter (H/m), or equivalently in newtons per ampere squared (N⋅A −2 ).

### Ohm

Ωohmsmegohm
:in which the following additional derived units occur: coulomb (C), farad (F), joule (J), weber (Wb), tesla (T), volt (V), hertz (Hz), and ohm .
in which the following units appear: volt (V), ampere (A), siemens (S), watt (W), second (s), farad (F), henry (H), joule (J), kilogram (kg), metre (m), and coulomb (C).

### Tesla (unit)

teslaTteslas
:in which the following additional derived units occur: coulomb (C), farad (F), joule (J), weber (Wb), tesla (T), volt (V), hertz (Hz), and ohm .

### Inductor

inductorscoilinductive
* Inductor
In the International System of Units (SI), the unit of inductance is the henry (H) named for 19th century American scientist Joseph Henry.

### Ampere

AmAamp
If a current of 1 ampere flowing through the coil produces flux linkage of 1 weber turn, the coil has a self inductance of 1 henry.‌ The unit is named after Joseph Henry (1797–1878), the American scientist who discovered electromagnetic induction independently of and at about the same time as Michael Faraday (1791–1867) in England. The henry is a derived unit based on four of the seven base units of the International System of Units: kilogram (kg), metre (m), second (s), and ampere (A). The inductance of an electric circuit is one henry when an electric current that is changing at one ampere per second results in an electromotive force of one volt across the inductor:

If a current of 1 ampere flowing through the coil produces flux linkage of 1 weber turn, the coil has a self inductance of 1 henry.‌ The unit is named after Joseph Henry (1797–1878), the American scientist who discovered electromagnetic induction independently of and at about the same time as Michael Faraday (1791–1867) in England.

### Electric current

currentelectrical currentcurrents
The inductance of an electric circuit is one henry when an electric current that is changing at one ampere per second results in an electromotive force of one volt across the inductor:

### Second

ssecmegasecond
The henry is a derived unit based on four of the seven base units of the International System of Units: kilogram (kg), metre (m), second (s), and ampere (A). The inductance of an electric circuit is one henry when an electric current that is changing at one ampere per second results in an electromotive force of one volt across the inductor:

### Electromotive force

EMFelectromotive force (EMF)
The inductance of an electric circuit is one henry when an electric current that is changing at one ampere per second results in an electromotive force of one volt across the inductor:

### Volt

VkVvolts
:in which the following additional derived units occur: coulomb (C), farad (F), joule (J), weber (Wb), tesla (T), volt (V), hertz (Hz), and ohm . The inductance of an electric circuit is one henry when an electric current that is changing at one ampere per second results in an electromotive force of one volt across the inductor:

### Metre

metermmetres
The henry is a derived unit based on four of the seven base units of the International System of Units: kilogram (kg), metre (m), second (s), and ampere (A).

### Coulomb

CPicoCoulomBExacoulomb
:in which the following additional derived units occur: coulomb (C), farad (F), joule (J), weber (Wb), tesla (T), volt (V), hertz (Hz), and ohm .

:in which the following additional derived units occur: coulomb (C), farad (F), joule (J), weber (Wb), tesla (T), volt (V), hertz (Hz), and ohm .

### Hertz

MHzkHzHz
:in which the following additional derived units occur: coulomb (C), farad (F), joule (J), weber (Wb), tesla (T), volt (V), hertz (Hz), and ohm .

### National Institute of Standards and Technology

NISTNational Bureau of StandardsBureau of Standards
The United States National Institute of Standards and Technology recommends users writing in English to use the plural as henries.

### Solenoid

solenoidselectromechanical solenoidmagnetizing current loop
Formulas can be used to calculate the inductance of many common arrangements of conductors, such as parallel wires, or a solenoid.

### Wire

stranded wireInsulated wirewire products

### Magnetic core

core lossiron coresoft iron