Faraday’s law is related to two areas of science: electricity and magnetism. In this sense, this law states that the induced voltage is equivalent to the variation in time of a magnetic field . In other words, the electromotive force is equal to the change in magnetic flux over time.
Understanding how an electric motor works from Faraday’s law
When we have a magnet with two different poles, they produce a magnetic field. When inserting the magnet into a coil, the variation of the magnetic flux over time produces a certain voltage, but if the magnet stays away from the coil, no voltage change occurs. This phenomenon can be explained by Faraday’s law, as a magnetic change that varies in time produces a voltage. This principle explains, in turn, the operation of the electromagnetic induction that takes place in a motor. Faraday’s Law
How was Faraday’s law arrived at?
In 1820, Danish scientist Hans Christian Oersted demonstrated that an electrical current alters a compass needle. From this discovery, Michael Faraday thought that if a current could alter a magnetic field it would mean that a magnetic field could also generate an electric current.
For more than ten years Faraday tried to demonstrate his initial hypothesis , and finally managed to pass a magnet through the interior of a solenoid, which was connected to a galvanometer.
He noticed that by quickly moving the magnet, the needle of the galvanometer also moved. This experiment was translated in parallel into a double technological advance: the development of generators and electric motors.
This British scientist is recognized as one of the great men of science of the 19th century. In addition to the law that expresses the relationship between electricity and magnetism, it also brought other relevant contributions. He developed a method that allowed some gases to liquefy if they were subjected to a certain pressure. On the other hand, he boosted organic chemistry , as he was the discoverer of a new compound: benzene. He brought important contributions to the further development of the electromagnetic theory of light (Faraday noted that a magnetic field can alter a beam of light). Faraday’s Law
Finally, he formulated the laws of electrolysis , which establish the relationship between chemical processes and electricity.
Michael Faraday was not a theoretical scientist like so many others, since throughout his life he gave lectures and conferences to spread science among younger people. His interventions were known as “Friday Evening Discourses” (lectures in sexta- afternoons fair ). Faraday’s Law