Magnets And Their Qualities

Magnets are materials or objects which have a field around them which attracts other objects or materials constructed from materials that are ferromagnetic.  One such common ferromagnetic material is iron.  Also, magnets can repel and attract other magnets.  It is usually only solids which become magnetized but liquid can also become magnetized when containting small particals which are ferromagnetic and near a magnetic field.  This kind of luquid is termed ferrofluid.  Materials which are not ferromagnetic also respond to magetic fields but not enough to be be labeled as magnetic.

Most magnetics are permanent and retain their magnetic fields without the need for another magnetic field to be present.  This are usually constructed of cobalt, iron, or nickel.  Some substances such as lodestone are naturally magnetized, however most perminant magnets are made by putting a powerful magnetic field on a ferromagetic material.  Ferromagnetic materials may be considered "hard" or "soft" depending upon their magnetic ability.  A soft substance (i.e. annealed iron) may be magnetized however it will lose the magnetic field quickly if it is not near other magnets.

Magnets were originally used for navigational purposes in compasses.  Today we think about magnets as a compass or a device to hold papers to metal surfaces like a refrigerator magnet.  However there are so many more ways to use them.  For example: magnetic tapes are utilized to put information on cassette and VHS tapes, and credit and ATM cards.  Computers utilize magetic materials as well.  The hard disk utilizes a drive shaft which rotates, which is surrounded by magnets.  It also has a ferrofluid in the space between the magnets and the shaft.  This has it act like a liquid seal.  Magnets can also be utilize in microphones, speakers, televisions, transformers, and generators.  Magnetic resonance imaging are used in hospitals in order to look at organs without surgery.

A special kind of magnets is the electromagnet which has a magnetic field made by an electric current.  Typically a coild wire with electric current going through it is twisted around an iron core, amplifying the strength of the field made by the electric current going through it.  A great advantage to this magnet is that you may control the strength by controlling the current of electricity going through it.  This magnet is used mostly in computers.


There are many health concerns about being exposed to a lot of electromagetic radiations yet magnets are very beneficial to society.  Aside from technological applications, magnets may be used for toys, education, and as well as the arts.  Artists around the world make moving art from magnets all the time.  Many new uses are being found constantly for magnets in today's ever growing and changing world.