Oersted's Experiment

In 1820, Dutch scientist Hans Christian Ørsted revolutionized physics with the twitch of a compass needle, revealing the connection between electricity and magnetism. When a compass needle is deflected from magnetic north as an electric current is switched on and off, it shows that a wire carrying an electric current produces magnetic fields around it. This demonstrated a direct relationship between electricity and magnetism. Ørsted was the first to show that an electric current can disturb a magnetic compass needle, proving that moving electricity produces magnetism. The direction of the needle's deflection can be determined by the SNOW rule. According to this rule, when current flows through a conductor from South to North and the wire is positioned over the magnetic needle, the north pole of the needle will deflect toward the West.