This topic accounts for approximately 9% of your exam marks.
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Stable9%
Magnetic field patterns, the motor effect and Fleming's Left-Hand Rule tested in most series.
Permanent magnets
A permanent magnet is made from a magnetically hard material (like steel or a special rare-earth alloy)
It produces its own magnetic field and keeps doing so even when no other magnet is nearby
A permanent magnet does not need a current to work
Induced magnets
An induced magnet is a piece of magnetic material that has been temporarily turned into a magnet by sitting in another magnet's field
The end of the induced magnet closest to the inducing magnet's pole takes the opposite sign (so the two are attracted)
The induced magnetism is lost almost as soon as the original magnet is removed, so soft iron releases its magnetism within a fraction of a second
Induced magnetism is why a paperclip will hang from a bar magnet, and a second paperclip can then hang from the first one, and so on, forming a short chain. Each clip is briefly magnetised by the one above it