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: A [[Bar Magnet|bar magnet]] is a '''permanent magnet'''.
: '''Permanent magnets''' are used in a electrical [[D.C. Motor|motor]]s.
: A [[magnet]] is made of several small [[Magnetic Domain|magnetic domains]] which are regions in the [[magnet]] which act as smaller [[magnet]]s. In a '''permanent magnet''' these [[Magnetic Domain|magnetic domains]] are fixed in place and need [[energy]] to change their [[magnet]]ic direction.
: A '''permanent magnet''' can only lose its [[Magnetic Field|magnetic field]] under certain conditions:
*When it is struck with a sudden [[force]].
*When it is [[heated]].
*When an extremely strong external [[Magnetic Field|magnetic field]] is applied.
{| class="wikitable"
|-
|[[File:MagneticDomainAligned.png|center|300px]]
|[[File:MagneticDomainUnaligned.png|center|300px]]
|-
| style="height:20px; width:200px; text-align:center;" |When [[Magnetic Domain|magnetic domains]] are aligned the [[object]] has an external [[Magnetic Field|magnetic field]] so it acts like a [[magnet]].
| style="height:20px; width:200px; text-align:center;" |When the [[Magnetic Domain|magnetic domains]] are not aligned there is no external [[Magnetic Field|magnetic field]] because the effect of the [[Magnetic Domain|magnetic domains]] cancels out.
|}