When did Hans Christian Oersted discover that the flow of electric current in a wire could deflect a nearby magnetic compass needle?
Show answer & explanation
Correct answer: D
Explanation
The correct answer is Option 4 i.e. 1820.
Hans Christian Oersted made his groundbreaking discovery in 1820, when he observed that an electric current flowing through a wire caused a nearby magnetic compass needle to deflect. This experiment demonstrated, for the first time, a direct relationship between electricity and magnetism, laying the foundation of electromagnetism. Oersted’s finding revolutionized science, inspiring further research by physicists like André-Marie Ampère and Michael Faraday. His work bridged two previously separate fields, ultimately leading to major technological advancements in electrical engineering and modern physics.