Physics · Ch 3 — Magnetism and Magnetic Effects of Electric Current
Oersted Experiment
Oersted Experiment
In 1820, while preparing a physics lecture, Hans Christian Oersted noticed that an electric current flowing through a wire deflects a nearby magnetic compass needle. Careful investigation showed the deflection is caused by a genuine magnetic field produced around the current-carrying conductor, and that reversing the current reverses the direction of deflection. This single observation established that electricity and …
What this figure shows. Two panels of a straight wire laid over a magnetic compass. In the first panel, no current flows and the compass needle points along its normal north-south rest direction, undisturbed. In the second panel, once a current is switched on through the wire, the needle swings around to a new deflected direction, showing that the current itself is producing a magnetic field strong enough to overpower the ne …