4.7 KiB
| title | chunk | source | category | tags | date_saved | instance |
|---|---|---|---|---|---|---|
| Hans Christian Ørsted | 1/3 | https://en.wikipedia.org/wiki/Hans_Christian_Ørsted | reference | science, encyclopedia | 2026-05-05T06:46:24.432145+00:00 | kb-cron |
Hans Christian Ørsted (Danish: [ˈɶɐ̯steð] ; 14 August 1777 – 9 March 1851), sometimes transliterated as Oersted ( UR-sted), was a Danish chemist and physicist who discovered that electric currents create magnetic fields. This phenomenon is known as Oersted's law. He also discovered aluminium, a chemical element. A leader of the Danish Golden Age, Ørsted was a close friend of Hans Christian Andersen and the brother of politician and jurist Anders Sandøe Ørsted, who served as Prime Minister of Denmark from 1853 to 1854.
== Early life and studies ==
Ørsted was born in Rudkøbing in 1777. As a young boy he developed an interest in science while working for his father, who was a pharmacist in the town's pharmacy. He and his brother Anders received most of their early education through self-study at home, going to Copenhagen in 1793 to take entrance exams for the University of Copenhagen, where both brothers excelled academically. By 1796, Ørsted had been awarded honors for his papers in both aesthetics and physics. He earned his doctorate in 1799 for a dissertation based on the works of Kant entitled The Architectonics of Natural Metaphysics. In 1800, Alessandro Volta reported his invention of the voltaic pile, which inspired Ørsted to investigate the nature of electricity and to conduct his first electrical experiments. In 1801, Ørsted received a travel scholarship and public grant which enabled him to spend three years traveling across Europe. He toured science headquarters throughout the continent, including in Berlin and Paris. In Germany, Ørsted met Johann Wilhelm Ritter, a physicist who believed there was a connection between electricity and magnetism. This idea made sense to Ørsted as he subscribed to Kantian thought regarding the unity of nature. Ørsted's conversations with Ritter drew him into the study of physics. He became a professor at the University of Copenhagen in 1806 and continued research on electric currents and acoustics. Under his guidance the university developed a comprehensive physics and chemistry program and established new laboratories. Ørsted welcomed William Christopher Zeise to his family home in autumn 1806. He granted Zeise a position as his lecturing assistant and took the young chemist under his tutelage. In 1812, Ørsted again visited Germany and France after publishing Videnskaben om Naturens Almindelige Love and Første Indledning til den Almindelige Naturlære (1811). Ørsted was the first modern thinker to explicitly describe and name the thought experiment. He used the Latin-German term Gedankenexperiment circa 1812 and the German term Gedankenversuch in 1820. In 1819 Ørsted was the first to extract piperine and subsequently name it. He extracted it from Piper nigrum, the plant from which are obtained both white and black pepper. Ørsted designed a new type of piezometer to measure the compressibility of liquids in 1822.
== Electromagnetism ==
In 1820, Ørsted published his discovery that a compass needle was deflected from magnetic north by a nearby electric current, confirming a direct relationship between electricity and magnetism. The often reported story that Ørsted made this discovery incidentally during a lecture is a myth. He had, in fact, been looking for a connection between electricity and magnetism since 1818, but was quite confused by the results he was obtaining. His initial interpretation was that magnetic effects radiate from all sides of a wire carrying an electric current, as do light and heat. Three months later, he began more intensive investigations and soon thereafter published his findings, showing that an electric current produces a circular magnetic field as it flows through a wire. For his discovery, the Royal Society of London awarded Ørsted the Copley Medal in 1820 and the French Academy granted him 3,000 francs. Ørsted's findings stirred much research into electrodynamics throughout the scientific community, influencing French physicist André-Marie Ampère's developments of a single mathematical formula to represent the magnetic forces between current-carrying conductors. Ørsted's work also represented a major step toward a unified concept of energy. The Ørsted effect brought about a communications revolution due to its application to the electric telegraph. The possibility of such a telegraph was suggested almost immediately by mathematician Pierre-Simon Laplace and Ampère presented a paper based on Laplace's idea the same year as Ørsted's discovery. However, it was almost two decades before it became a commercial reality.
== Later years ==