Chapter 21: Magnetism and Electromagnetism

Magnetic materials: iron, steel, nickel, cobalt, manganese and aluminum
Magnetism is the ability to attract and pick up other magnetic substances
Permanent magnets are usually made of steel or a range of of modern magnetically 'hard' materials
Hard magnets are used for things like magnets that we want something to stay magnetised (permanent magnets)
Soft magnetic materials are used when we need something to magnetise and demagnetise easily (temporary magnets)
Unmagnetised iron, steel and a few other elements and their alloys or compounds can be attracted to a magnet. The permanent magnet induces magnetic effect in the unmagnetised iron with an unlike pole nearest the pole of the magnet. Therefore, unmagnetised materials like iron are always attracted to magnets, never repelled
The lines that the iron filings form when placed around a magnet, show the direction of the force that would act on a small North pole placed at any point in the field, so the arrows on the lines always point away from the North pole towards the South pole
The direction of the force at any point…

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