## Magnetic field |

A **magnetic field** is a
*direction* and a *magnitude* (or strength), so it is represented by a
**B** and **H**, where, in the
**H** is measured in units of
**B** is measured in
**H** is a field introduced to account for the effects of
**B** and **H** are the same aside from units; but in a material with a magnetization (denoted by the vector **M**), **B**/ is equal to the sum of **H** and **M**.

Magnetic fields are produced by moving
^{
[1]}^{
[2]} Magnetic fields and

In everyday life, magnetic fields are most often encountered as a

Magnetic fields are widely used throughout modern technology, particularly in

- history
- definitions, units, and measurement
- magnetic field lines
- magnetic field and permanent magnets
- magnetic field and electric currents
- relation between h and b
- energy stored in magnetic fields
- electromagnetism: the relationship between magnetic and electric fields
- important uses and examples of magnetic field
- see also
- notes
- references
- further reading
- external links

Although magnets and magnetism were known much earlier, the study of magnetic fields began in 1269 when French scholar
^{
[nb 1]} Noting that the resulting field lines crossed at two points he named those points 'poles' in analogy to Earth's poles. He also clearly articulated the principle that magnets always have both a north and south pole, no matter how finely one slices them.

Almost three centuries later,
^{
[3]} Published in 1600, Gilbert's work, *
De Magnete*, helped to establish magnetism as a science.

In 1750,
^{
[4]}
^{
[5]} Building on this force between poles,
^{
[6]} In this model, a magnetic **H**-field is produced by 'magnetic poles' and magnetism is due to small pairs of north/south magnetic poles.

Three discoveries challenged this foundation of magnetism, though. First, in 1819,

Extending these experiments, Ampère published his own successful model of magnetism in 1825. In it, he showed the equivalence of electrical currents to magnets^{
[7]} and proposed that magnetism is due to perpetually flowing loops of current instead of the dipoles of magnetic charge in Poisson's model.^{
[nb 2]} This has the additional benefit of explaining why magnetic charge can not be isolated. Further, Ampère derived both

In 1831,
^{
[8]} In the process, he introduced the

In 1850,
**H** and **B**. The former applied to Poisson's model and the latter to Ampère's model and induction.^{
[9]} Further, he derived how **H** and **B** relate to each other.

The reason **H** and **B** are used for the two magnetic fields has been a source of some debate among science historians. Most agree that Kelvin avoided **M** to prevent confusion with the SI fundamental unit of length, the
^{
[10]}^{
[11]}

Between 1861 and 1865,
*
On Physical Lines of Force* in 1861. These equations were valid although incomplete. Maxwell completed his set of equations in his later 1865 paper *
A Dynamical Theory of the Electromagnetic Field* and demonstrated the fact that light is an

The twentieth century extended electrodynamics to include relativity and quantum mechanics.

Other Languages

Afrikaans: Magneetveld

Alemannisch: Magnetfeld

አማርኛ: መግነጢስ መስክ

العربية: حقل مغناطيسي

aragonés: Campo magnetico

অসমীয়া: চুম্বকীয় ক্ষেত্ৰ

asturianu: Campu magnéticu

azərbaycanca: Maqnit sahəsi

تۆرکجه: مغناطیس مئیدانی

বাংলা: চৌম্বক ক্ষেত্র

башҡортса: Магнит ҡыры

беларуская: Магнітнае поле

беларуская (тарашкевіца): Магнітнае поле

български: Магнитно поле

bosanski: Magnetno polje

буряад: Суранзан орон

català: Camp magnètic

čeština: Magnetické pole

Cymraeg: Maes magnetig

dansk: Magnetfelt

Deutsch: Magnetfeld

eesti: Magnetväli

Ελληνικά: Μαγνητικό πεδίο

español: Campo magnético

Esperanto: Magneta kampo

estremeñu: Campu manéticu

euskara: Eremu magnetiko

فارسی: میدان مغناطیسی

Fiji Hindi: Magnetic field

français: Champ magnétique

Gaeilge: Réimse maighnéadach

galego: Campo magnético

ગુજરાતી: ચુંબકીયક્ષેત્ર

한국어: 자기장

Հայերեն: Մագնիսական դաշտ

हिन्दी: चुम्बकीय क्षेत्र

hrvatski: Magnetsko polje

Ido: Magnetala feldo

Bahasa Indonesia: Medan magnet

interlingua: Campo magnetic

íslenska: Segulsvið

italiano: Campo magnetico

עברית: שדה מגנטי

ქართული: მაგნიტური ველი

қазақша: Магнит өрісі

Kiswahili: Uga sumaku

Kreyòl ayisyen: Chan mayetik

лезги: Магнитдин чуьл

Latina: Campus magneticus

latviešu: Magnētiskais lauks

lietuvių: Magnetinis laukas

Limburgs: Magnetisch veldj

magyar: Mágneses mező

македонски: Магнетно поле

മലയാളം: കാന്തികക്ഷേത്രം

मराठी: चुंबकी क्षेत्र

Bahasa Melayu: Medan magnet

монгол: Соронзон орон

မြန်မာဘာသာ: သံလိုက်စက်ကွင်း

Nederlands: Magnetisch veld

नेपाली: चुम्बकीय क्षेत्र

日本語: 磁場

Nordfriisk: Magneetisk fial

norsk: Magnetfelt

norsk nynorsk: Magnetfelt

occitan: Camp magnetic

oʻzbekcha/ўзбекча: Magnit maydon

ਪੰਜਾਬੀ: ਚੁੰਬਕੀ ਖੇਤਰ

پنجابی: مقناطیسی میدان

polski: Pole magnetyczne

português: Campo magnético

română: Câmp magnetic

русиньскый: Маґнетічне поле

русский: Магнитное поле

Scots: Magnetic field

shqip: Fusha magnetike

sicilianu: Campu magneticu (artìculu 'n calabbrisi)

සිංහල: චුම්බක ක්ෂේත්රය

Simple English: Magnetic field

slovenčina: Magnetické pole

slovenščina: Magnetno polje

کوردی: بواری موگناتیسی

српски / srpski: Магнетно поље

srpskohrvatski / српскохрватски: Magnetno polje

Basa Sunda: Médan magnétik

suomi: Magneettikenttä

svenska: Magnetfält

தமிழ்: காந்தப் புலம்

татарча/tatarça: Магнит кыры

తెలుగు: అయస్కాంత క్షేత్రం

ไทย: สนามแม่เหล็ก

Türkçe: Manyetik alan

українська: Магнітне поле

اردو: مقناطیسی میدان

Tiếng Việt: Từ trường

Winaray: Palibot han batobarani

Wolof: Toolu bijjaakon

ייִדיש: מאגנעטיש פעלד

粵語: 磁場

中文: 磁場