Magnetism


Bar magnet

One of the fundamental properties of matter is magnetism. Magnetism is related to electricity. In fact, the fundamental cause of all magnetism effects is due to the movements of electric charges. Common materials for magnets are iron, steel, cobalt and nickel. They are suitable to make magnets due to their atomic structures.

  • An atom consists of a central, positively charged nucleus surrounded by negatively charged electrons. A common view of the electrons is that they orbit around the central nucleus, while spinning on their axes. This view is not exactly correct, but its alright at this level. Due to the charge on the electrons, the movements of these electrons will give rise to magnetic effects. These magnetic effects can be seen as tiny atomic magnets.
  • The tiny magnetic effects occurs in all substances. Then, why aren’t all substances magnetic? This is due to their atomic structures. In those materials, the electrons are arranged in configurations that result in the magnetic effects cancelling out one another.
  • Once those tiny atomic magnets are aligned properly, it will give rise to a strong combined magnetic effect. At this point, the substance is considered to be magnetised and is a proper magnet.
  • Lodestone is the only natural substance that behaves as a magnet. Magnetic materials like steel and iron can be made into magnets.

 


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