Back in 1820, a scientist named Hans-Christian Oerstend lived in a country called Denmark. He experimented with electric current and noticed that the current flowing through the wire causes a deflection of the magnetic needle on the device. This was the impetus for the invention of the electromagnet, which the world learned about from the monographs of another Danish inventor named Ulyam Sturgeon.
In 1825, Sturgeon wrapped copper wire around an iron rod bent like a horseshoe. By sending an electric current through the wire, the scientist was convinced that the horseshoe acquired magnetic properties unusual for it before. However, as soon as he turned off the current, the magnetic phenomena immediately disappeared. Sturgeon managed to lift a piece of iron weighing 9 pounds (4 kilograms) with such a simple electromagnet, which caused the delight of his contemporaries.
In 1827, the American Joseph Henry discovered that the more turns of a conductor wound on an iron base, the stronger the magnetic field created by this "apparatus" was, only the turns must be carefully isolated from each other. Henry found an extraordinary way out of this situation, he cut his wife's silk wedding dress into strips and wrapped them in turns of wire.
After three years of endless experiments and experiments, in 1831 Henry created an electromagnet that lifted a one and a half ton load into the air.
We soon realized that to insulate the wire, it was enough to cover it with varnish. It became possible with the help of an electromagnet to easily lift and move heavy metal loads. Very often, such electromagnetic washers are used in metallurgical production: in finished product shops and on scrap metal loading devices.
The electromagnet has also found application in many other industries. In particular, the world owes to Joseph Henry the birth of the first electric bell, the basis of which is a small electromagnet.
The principle on which the electric bell works is the work of a metal hammer, which quickly and frequently hits the bell of the bell. To do this, the electric bell device is made in such a way that when the button is pressed, an electric current arises in the circuit, under the action of which the electromagnet begins to pull the hammer on one side, and the spring on the other, the hammer often starts striking the bell cup and we hear a ringing. To do this, an electric current at a ringing magnet is fed through metal contacts that open when the electromagnet pulls the hammer in its direction, thereby interrupting applying current to the ring magnet, and the result is a melodic chime.
This is how, thanks to the perseverance and hard work of the American inventor, a miracle bell was born, which is installed near every front door around the world.
