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Magnets

Basics of a magnet
There are two poles of a magnet:
1. North Pole
2. South Pole
The North Pole:
The North Pole is that part of the magnet that is pointing at the Northern Cardinal of the earth. It is the part of the magnet, that is negative.
The Southern Pole:
The part of the magnet that is pointing at the Southern cardinal point of the earth is called the Southern Pole. It is the part of the magnet that is positive.

Attraction and repulsion of a magnet
Just as like charges repels and unlike charges attracts, so as it is in magnets. 
The like poles of a magnet, repels each other; while the unlike poles of a magnet,  attracts each other.
Take for example; the Northern pole of a magnet will attract the southern pole of another magnet, this is because they have different magnetic polarity.
Also, the Northern pole of Magnet A will repel the Northern pole of Magnet B, this is because both two magnets have the same magnetic polarity.

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