Electromagnetism
Year of Discovery: 1820
What Is It? An electric current creates a magnetic field and vice versa.
Who Discovered It? Hans Oersted
Why Is This One of the 100 Greatest?
Before 1820, the only known magnetism was the naturally occurring magnetism of
iron magnets and of lodestones—small, weak direction finders. Yet the modern world of
electric motors and electric generating power plants is muscled by powerful electromagnets. So is every hair dryer, mixer, and washing machine. Our industry, homes, and lives depend on electric motors—which all depend on electromagnetism.
This 1820 discovery has become one of the most important for defining the shape of
modern life. Oersted’s discovery opened the door to undreamed of possibilities for research
and scientific advancement. It made possible the work of electromagnetic giants such as
Andre Ampere and Michael Faraday.
How Was It Discovered?
Hans Oersted was born in 1777 in southern Denmark. He studied science at the university, but leaned far more toward philosophy. Oersted adopted the philosophy teachings of
John Ritter, who advocated a natural science belief that there was unity in all natural forces.
Oersted believed that he could trace all natural forces back to the Urkraft, or primary force.
When he was finally given a science teaching position (in 1813), he focused his research efforts on finding a way to trace all chemical reactions back to Urkraft in order to create a
natural unity in all of chemistry.
Research and interest in electricity mushroomed after Benjamin Franklin’s experiments with static electricity and sparks of energy created with Leyden jars. Then, in 1800,
Volta invented the battery and the world’s first continuous flow of electric current. Electricity became the scientific wonder of the world. Sixty-eight books on electricity were published between 1800 and 1820.
Only a few scientists suspected that there might be a connection between electricity
and magnetism. In 1776 and 1777 the Bavarian Academy of Sciences offered a prize to anyone who could answer the question: Is there a physical analogy between electrical and magnetic force? They found no winner. In 1808, the London Scientific Society made the same
offer. Again there was no winner.
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