In 1820, the Danish scientist Hans Christian Oersted did not imagine that with a simple experiment he would discover a physical principle of extreme importance for the operation of this type of motor. In this way, the scientist passed an electric current, produced by a normal heap, by a conductor wire and soon after approaching a compass of that wire. The needle, which acts magnetically, moved and aligned perpendicular to the thread. For Oersted, the event confirmed that around the wire, had a magnetic field, which acted on the field of the needle.
Thus, the relationship between magnetism and electricity was first established. The French physicist André-Marie Ampere, a genius of mathematics, after knowing the experiences of the Dane, began to create a law of electromagnetism, understanding that the lines of force created by the electrified wire, the magnetic field, are circular, that is, Form a kind of invisible cylinder around the driver. T2535173S
Up until now, the magnetic field had been thought to move only in a straight line, as from one magnet to another. In the connection between electricity and magnetism, there was Englishman Michael Faraday. He valued experience as evidence of natural phenomena. It was thanks to his experiences and his curiosity, he was able to demonstrate in 1822 the circular magnetic field.