Editing Electromagnet (section)

{{Short description|Magnet that creates a magnetic field through an electric current}}
{{Broader|Electromagnetism}}
{{pp-move|small=yes}}
{{Infobox electronic component
| name              = Electromagnet
| image             = Electromagnet-with-9V-battery.jpg
| caption           = Homemade electromagnet with 9V battery
| type              = [[Magnet]]
| working_principle = [[Oersted's law]]
| inventor          = [[William Sturgeon]] 
| invention_Year    = 1824
| symbol            = [[File:Electric-symbol-electromagnet.png]]
}}
[[File:Simple electromagnet2.gif|thumb|A simple electromagnet consisting of a coil of wire wrapped around an iron core. A core of ferromagnetic material like iron serves to increase the magnetic field created.<ref name="Hyperphysics" /> The strength of the magnetic field generated is proportional to the amount of current through the winding.<ref name="Hyperphysics" />]]

An '''electromagnet''' is a type of [[magnet]] in which the [[magnetic field]] is produced by an [[electric current]]. Electromagnets usually consist of wire (likely copper) wound into a [[electromagnetic coil|coil]]. A current through the wire creates a magnetic field which is concentrated along the center of the coil. The magnetic field disappears when the current is turned off. The wire turns are often wound around a [[magnetic core]] made from a [[ferromagnetic]] or [[ferrimagnetic]] material such as [[iron]]; the magnetic core concentrates the [[magnetic flux]] and makes a more powerful magnet.

The main advantage of an electromagnet over a [[permanent magnet]] is that the magnetic field can be quickly changed by controlling the amount of electric current in the winding. However, unlike a permanent magnet, which needs no power, an electromagnet requires a continuous supply of current to maintain the magnetic field.

Electromagnets are widely used as components of other electrical devices, such as [[Electric motor|motors]], [[Electric generator|generators]], [[Solenoid#Applications|electromechanical solenoid]]s, [[relay]]s, [[loudspeaker]]s, [[hard disk]]s, [[Magnetic resonance imaging|MRI machines]], scientific instruments, and [[magnetic separation]] equipment. Electromagnets are also employed in industry for picking up and moving heavy iron objects such as scrap iron and steel.<ref name="Merzouki" />