Force Between Current-Carrying Coils


To demonstrate that current-carrying coils produce magnetic fields and interact like bar magnets.◙


Mounted setup of two coils, battery with capacitor for current boost, switch, and bar magnet.◙





Two coils are aligned with their currents moving around in the same direction, so their magnet fields will be North-to-South. They will attract each other when the current is started by pushing the switch. Changing the wires on the top can put any combination of magnetic poles adjacent, getting either attraction or repulsion. A small bar magnet, included with the demonstration, can be used to see the forces between one of the coils and the magnet, again using any combination of magnetic poles.