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 Form 4 Physics: Electromagnetic induction online video lessons

Eddy currents as used in electromagnetic induction and their causes

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Answer Text:
Eddy currents
-They are composed of loops of current which have a magnetic effect opposing the force producing them. When a copper plate with slits is
used the loops are cut off and hence the effective currents are drastically reduced and so is the opposing force.
figelectromagneticinduction2582020926.JPG

figelectromagneticinduction2582020927.JPG
-Practically eddy currents are reduced by laminating metal plates. Armatures of electric generators and motors are wound on laminated soft iron
cores. The lamination slices, which are quite thin are glued together by a non-conducting glue and this reduces eddy currents to an almost
negligible value. Eddy currents are useful in moving coil meters to damp the oscillations of the armature when the current is switched off.


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