Facts About Magnets

Magnet Facts

• The Earth is like a large magnet with a magnetic field. The north magnetic pole is in Canada. The south magnetic pole is in Antarctica.


• No one knows why the earth became magnetized. Other planets and stars also have a magnetic field. Scientists think that these planets and stars that are magnetic all have a core made of iron or another metal that can become magnetized.


• There are three special transition metals in the Period Table of elements. Iron, cobalt and nickel are the only known elements to produce a magnetic field.


• People names the magnetic rocks. A magnetite is a type of rock that contains iron which is possible to magnetize.


• A lodestone has rare pieces of magnetite that can attract iron.


• There are a total of 17 rare earth elements in the periodic table. In the 1960s scientists discovered that using some of the rare earth elements such as yttrium, combined with cobalt resulted in a very strong magnet.


• Scientists measure the strength of magnetic force of a material in the unit Tesla (named after Nikola Tesla).


• It is possible to remove the magnetism from iron by heating it up. To remove iron's magnetic properties heat it to 1500 degrees Fahrenheit (815 degrees Celsius). Removal of magnetism is useful for some machines.

History of Magnets

• Naturally magnetic lodestones were found in an area of Greece called Magnesia
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• In the 1100s Lodestones are used for navigation


• In 1269 Petus de Maricourt discovers that magnets have two poles.


• In 1600 William Gilbert discovers Earth's magnetism and magnetic poles


• In 1820 Hans Christian Oersted discovers that wire carrying an electrical current creates a magnetic field


• In the late 1800s, William Thompson (Lord Kelvin), created the most accurate compass for the time. It was a liquid compass where alcohol was used for the liquid so it would not freeze. The magnetic needle was magnetized by a lodestone.
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• In 1930 the Japanese discover the material ferrite which is a compound containing ceramic material and iron. Ferrite is used to make a strong permanent magnet.


• In 1931, Mishima, a Japanese scientist discovers that a compound containing aluminum, nickel and cobalt makes a stronger magnetic force than ferrite. The compound is named after the 3 elements, alnico.