round the nucleus. When electrons move they produce small magnetic fields. Usually electrons come in pairs. These pairs move in opposite directions and their magnetic fields cancel each other out. A piece of iron has a large number of unpaired electrons. In iron, the atoms align their magnetic fields with those of nearby atoms to form small magnetic areas called magnetic domains. When the domains are arranged randomly, in a piece of iron or another magnetic material, the material is not magnetized. When the magnetic material is placed in a strong magnetic field, the domains line up. The north poles of the domains all face in one direction, and the material acts as a magnet.Scientists have also noticed a link between magnetism and electricity. In 1820, a Danish scientist named Hans Christian Oersted made an amazing discovery. He found that when he placed a compass near a piece of wire that had electricity running through it, the compass needle changed direction. This showed that electricity and magnetism were related. Soon after Oersteds discovery of the relationship between electricity and magnetism, French scientist Andre Marie Ampere began performing a number of experiments based on Oersteds work. He found that when a wire carrying an electric current was bent into a loop, the magnetic force around it seemed to become stronger. Then he wound the wire into a coil and found that the coil acted like a bar magnet. He showed that a piece of iron inserted in the coil became strongly magnetized. Other scientists tried different ways to make magnets stronger. By the 1830s, they were able to make an electromagnet that could lift over a ton of iron. Another important discovery made by scientists regarding the connection between magnetism and electricity was that by Michael Faraday (1791- 1867) an English physicist. His ideas of electrical induction led the way to the development of electric generators (machines that convert me...
