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===Compared to a Bar Magnet===
{| class="wikitable"
| style="height:20px; width:200px300px; text-align:center;" |'''Advantages of an Electromagnet over a Bar Magnet'''| style="height:20px; width:200px300px; text-align:center;" |'''Disadvantages of an Electromagnet over compared to a Bar Magnet'''
|-
| style="height:20px; width:200px300px; text-align:centerleft;" |
Changing the [[Electrical Current|current]] can change the strength of an [[electromagnet]].
The direction of the [[Magnetic Field|magnetic field]] can be changed in an [[electromagnet]] by changing the direction of the [[Electrical Current|current]].
| style="height:20px; width:200px300px; text-align:centerleft;" |
[[Electromagnet]]s require a source of power to work.
[[Electromagnet]]s increase in [[temperature]] as they are used.
|}
==Key Stage 4==
===Meaning===
An [[electromagnet]] is a [[magnet]] made from a [[solenoid]] and a [[Soft Iron|soft iron]] core.
===About Electromagnets===
: [[Electromagnet]]s only work when there is a [[Direct Current|direct current]] passing through the [[solenoid]]
: An [[electromagnet]] can be turned off and on.
: The strength of an [[electromagnet]] depends on; the number of coils of [[wire]] in the [[solenoid]], the [[Electrical Current|current]] through the [[solenoid]] and how easily the [[Soft Iron|soft iron]] core can be [[Magnetise|magnetised]].
*The more coils of [[wire]] in the [[solenoid]] the stronger the [[electromagnet]].
*The greater the [[Electrical Current|current]] through the [[solenoid]] the stronger the [[electromagnet]].
*The more easily [[Magnetise|magnetised]] the [[Soft Iron|soft iron]] core, the stronger the [[electromagnet]].
{| class="wikitable"
|-
|[[File:MagneticFieldLinesElectromagnet.png|center|400px]]
|-
| style="height:20px; width:200px; text-align:center;" |The direction of the [[Magnetic Field|magnetic field]] can be changed by changing the direction of the [[Electrical Current|current]].
|}
===Compared to a Bar Magnet===
{| class="wikitable"
| style="height:20px; width:300px; text-align:center;" |'''Advantages of an Electromagnet over a Bar Magnet'''
| style="height:20px; width:300px; text-align:center;" |'''Disadvantages of an Electromagnet compared to a Bar Magnet'''
|-
| style="height:20px; width:300px; text-align:left;" |
Changing the [[Electrical Current|current]] can change the strength of an [[electromagnet]].
An [[electromagnet]] can be turned on an off by turning the [[Electrical Current|current]] on and off.
The direction of the [[Magnetic Field|magnetic field]] can be changed in an [[electromagnet]] by changing the direction of the [[Electrical Current|current]].
| style="height:20px; width:300px; text-align:left;" |
[[Electromagnet]]s require a source of power to work.
[[Electromagnet]]s increase in [[temperature]] as they are used.
|}
===Applications===
{| class="wikitable"
|-
|[[File:RelayDiagram1.png|center|300px]]
|[[File:RelayDiagram2.png|center|300px]]
|-
| style="height:20px; width:200px; text-align:center;" colspan = "2"|When the switch is closed the [[electromagnet]] pulls the [[Iron]] armature towards it. This causes the the two large electrical contacts to touch. When the [[switch]] is open the [[electromagnet]] turns off and the contacts separate.
This is used for safety reasons so that a [[switch]] can be used to operate a [[circuit]] with a very large [[Electrical Current|current]] indirectly.
|}
{| class="wikitable"
|-
|[[File:BellDiagram1.png|center|300px]]
|[[File:BellDiagram2.png|center|300px]]
|-
| style="height:20px; width:200px; text-align:center;" colspan = "2"|When the [[switch]] is closed the [[electromagnet]] pulls the [[Iron]] armature towards it. This causes the a [[metal]] arm to bend and the striker to hit the bell. When the arm bends the [[circuit]] is broken and the [[electromagnet]] turns off. This allows the striker to move back away from the bell, where electrical contact is made and the process repeats.
|}
===References===
====AQA====
:[https://www.amazon.co.uk/gp/product/1782946403/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782946403&linkCode=as2&tag=nrjc-21&linkId=32a0abb60dff015b15b50e9b1d7b4644 ''Electromagnets, page 219, GCSE Combined Science Trilogy; Physics, CGP, AQA '']
:[https://www.amazon.co.uk/gp/product/019835939X/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=019835939X&linkCode=as2&tag=nrjc-21&linkId=57e96876985fc39b1a3d8a3e3dc238b6 ''Electromagnets, pages 217-219, GCSE Physics; Third Edition, Oxford University Press, AQA '']
:[https://www.amazon.co.uk/gp/product/1471851370/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1471851370&linkCode=as2&tag=nrjc-21&linkId=01c69b0ae058f809cf636033e6ba793e ''Electromagnets, pages 225-6. GCSE Physics, Hodder, AQA '']
:[https://www.amazon.co.uk/gp/product/1471851362/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1471851362&linkCode=as2&tag=nrjc-21&linkId=7d78d70a2044ee9982dae010c94af92a ''Electromagnets, pages 279, GCSE Combined Science Trilogy 2, Hodder, AQA '']
:[https://www.amazon.co.uk/gp/product/1782945970/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945970&linkCode=as2&tag=nrjc-21&linkId=a120d24dcc7cc7a58192069a3aafc1d2 ''Electromagnets, pages 292, 293, GCSE Physics; The Complete 9-1 Course for AQA, CGP, AQA '']
====Edexcel====
:[https://www.amazon.co.uk/gp/product/1292120223/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1292120223&linkCode=as2&tag=nrjc-21&linkId=068ecf40278c32406a7f1c6e66751417 ''Electromagnets, page 171, GCSE Physics, Pearson Edexcel '']
:[https://www.amazon.co.uk/gp/product/1782945741/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945741&linkCode=as2&tag=nrjc-21&linkId=30da4f2178da182547b62a7329d13b57 ''Electromagnets, page 198, GCSE Combined Science; The Revision Guide, CGP, Edexcel '']
:[https://www.amazon.co.uk/gp/product/1292120193/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1292120193&linkCode=as2&tag=nrjc-21&linkId=572df39392fb4200db8391d98ae6314e ''Electromagnets, page 405, GCSE Combined Science, Pearson Edexcel '']
:[https://www.amazon.co.uk/gp/product/1782945733/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945733&linkCode=as2&tag=nrjc-21&linkId=2a2dbec9db6bf5766c0458d908fa0a52 ''Electromagnets, page 88, GCSE Physics; The Revision Guide, CGP, Edexcel '']
:[https://www.amazon.co.uk/gp/product/1782948163/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782948163&linkCode=as2&tag=nrjc-21&linkId=0fdbfd5dd397d6e24a9dfb250f08587f ''Electromagnets, pages 270-272, GCSE Physics, CGP, Edexcel '']
:[https://www.amazon.co.uk/gp/product/1782948163/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782948163&linkCode=as2&tag=nrjc-21&linkId=0fdbfd5dd397d6e24a9dfb250f08587f ''Electromagnets; uses, pages 271-279, GCSE Physics, CGP, Edexcel '']
====OCR====
:[https://www.amazon.co.uk/gp/product/0198359837/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=0198359837&linkCode=as2&tag=nrjc-21&linkId=3c4229e8b023b2b60768e7ea2307cc6f ''Electromagnets, pages 123, Gateway GCSE Physics, Oxford, OCR '']