When a magnet is brought close to another magnet it is either repelled or attracted to the magnet. A magnet will be attracted to another magnet if unlike poles are approaching each other. They will repel if like poles are approaching each other. In 1819 a physists called Oersted discovered that a current carrying conductor behaves like a magnet (it can attract or repel other magnets). The experiment to prove this phenomenon has since been called the Oersted experiment.
The Oersted experiment involves placing a compass needle close to a conduct carrying current. When the switch is closed, the magnetic needle deflects indicating the presence of a magnetic field around a conductor carrying current.
The video below shows Oersted experiment:
Move to the side bench of the computer lab and perform the experiment set up for you by:
- Close the switch and observe the magnetic compass,
- Open the switch, Change the direction of the current by interchanging the terminals of the source of power, then close the switch again and observe the compass needle.