The classical magnet is a mineral called lodestone, which can be found in nature. It has a property to attract certain metallic objects and also in some cases can magnetize these objects themselves. The most common magnets are of course, made of iron.
A simple but very popular experiment in magnets can be done. By taking a bar magnet and placing it under a sheet of paper and then put some iron filings on the paper. As a result of the magnetic force around the magnet, the iron filings spread out in the direction of the magnetic force.
A magnet has two poles, North pole and South pole. Earth is also considered as a magnet and there is a north and south pole on earth too. That is the reason why, when a magnet is freely suspended the magnet orients itself to the geographic north pole and south pole showing us the exact the location of the poles. This is the basic principle behind the working of a magnetic needle in a compass.
The poles in a magnet are very similar to electric charge, in that opposite poles attract one another, just as positive and negative charges attract each other and like poles i.e. north pole repels north pole and south pole repels south pole.
There is a connection between magnetism and electricity which was discovered in the late eighteenth century. This discovery led to many experimentations which proved that magnetism and electricity cannot be separated and they lie in perpendicular to each other. It was also learned that one can be used to manipulate the other. This led to many experimentations by Michael Faraday who conducted many experiments with a moving-coil galvanometer which eventually gave rise to dynamo and then to the alternator and today’s huge power generation plants. The discovery of the relationship between magnetism and electricity proved to be a turning point in the history of modern human civilization.
Today, magnets are of great importance. Without magnets electricity could not be mass produced. Magnets or the magnetism is the key ingredient in motors which drive water, fuel and other liquids. Magnets are one of the main components in sound systems. Magnets are found in many devices that we use today, most importantly in MRI scanning or Magnetic Resonance Imaging which is one of the best diagnostic tools.
In recent times, magnetism is the key ingredient in maglev or Magnetic Levitation trains which are some of the fastest trains on earth have been manufactured thanks to strong electromagnets.
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