|Explanation||Hans Christian Ørstedt||Philipp Reis||Alessandro Volta||Enrico Fermi||Mario Corbino|
|Ettore Majorana||Luigi Galvani||Marija Aleksaite-Gimbutiene||Carl Auer von Welsbach|
Hans Christian Ørstedt
HC Oersteds experiment
The magnets, you could produce before 1820, wasnt very powerful compared to the ones you could find in nature. But in 1820 the Danish physicist, Hans Christian Oersted (1777-1875), discovered, that a magnetic sphere comes into existence around a wire, when an electric current is send through it.
From one of Oersteds pupils we know, he didnt like foreign words. He liked to start his lessons by translating the foreign words into Danish. That was impossible, therefore he invented his own Danish words for example ilt (oxygen), brint (hydrogen), rumfang (volume) and vægtfylde (specific gravity). In all he created over 2000 new words.
Oersted was fascinated by modern philosophy, and the thought that all nature in spite of its diversity is a unified whole. But he didnt accept a theory without trying it out first.
It was in the spirit of this philosophy, that one of the greatest physical questions of his time was: if possibly there was a relation between electricity and magnetism? Something seemed to show that this was the case, but nobody had been able to prove it.
From 1800-1820 Oersted experimented finding a method to create magnetism, by the means of electricity all without crucial or proving results.
But then .. on a spring day in 1820, when Oersted gave one of his many lectures about electricity, something happened. On a table stood among other things a compass and a voltaic cell. Suddenly Oersted stopped his lecture. On an impulse he investigated, if the magnetic needle could be affected by a live wire. When he held the wire lengthwise the magnetic needle, it turned to the side the electromagnetism was discovered!!! Oersted proof of the fact that there is a magnetic sphere around a live wire, was one of the most important discovery of that time and opened the way to the invention of electromagnetism.
How did the experiment turn out? The sphere lines from the magnet, which the electricity forms, affects the compass needle, which turns and tries to place its lines in the same direction . The compass needles direction is now abeam of the wire and the magnets north pole will turn in the direction of the sphere lines.
If you hold the wire below the compass needle, itll turn in the opposite direction. Of this you can conclude, that the sphere lines is placed like circles around the wire.
Oersted also invented a rule, which will tell you the direction of the lines :
Grab the wire with your right thumb, which is pointing in the direction of the electricity, then your fingers and the sphere lines will point in the same direction.
Life of Oersted
HC Oersteds parents had not so much money, so Oersted got a arithmetic book from his father, but Oersted had to give his knowledge to his little brother, Anders.
H. C. Oersted worked at the farther chemistry for 12 years. He was trained as a pharmacist, but he got an interest for the work in the laboratory and started reading everything about chemistry and other things as science. Gradually he was convinced that he wanted to study these things. The same would Oersteds little brother, Anders.
So they prepared to the admission to Copenhagen University. When they have studied a few months, they passed the exams with really goods marks.
Oersted began to study chemistry and physics, and he studied philosophy and aesthetics together with Anders. Copenhagen University had non exams in chemistry and physics, so Oersted instead passed his final university examination in 1797 (20 years old). The same year he won a university prize for an aesthetics subjects.
In 1798 Oersted got a prize for a subject again, this time for a medical project. In 1800 he took over a lecture in chemistry instead of the teacher Manthey, who was on a journey abroad.
The next summer, Oersted gets a Cappelske Grant and some money. He spend the money on a journey abroad, which lasted until 1804. The journey went to Germany, France, Belgium and Holland. The journey was a big inspiration for him.
After Oersted returned to Denmark he got a position in Copenhagen University, where he had to give lectures in physics for the next 3 years. He got 300 Danish dollars a year, but the pupils thought that he was very good.
In 1812-1813 he went on a journey abroad, first to Berlin, where he after 3 month read a book called Ansichten der cheemischen Naturgesetze. After that he went to Paris.
When he returned to Denmark in 1814, and he married a girl. Oersted was ordinated professor in 1817. The same year Oersted began testing some liquids and gases printing together, and when he constructed the well-known pressure gauge, which he called, in his own words, piezometer. He also discovered the element, aluminium, and its edification. On top of all this he was president of the society of physic dissemination.
A spring evening in 1820, Oersted gave a lecture, where he completed an experiment.
In 1824 discovered Oersted the element aluminium.
Oersted wanted a technological school. In 1829 Christian 6. founded a Technological Teacher institution, and Oersted was the manager until he died in 1851. Oersted also got the MET office and a mathematical science in the University.