In this classic demonstration of electromagnetic induction, an aluminum ringis propelled straight up a distance of 2 meters. The changing magnetic field from the AC power coil causes a changing magnetic flux through the aluminum ring. The induced emf in the ring sets up a current which produces a magnetic field which opposes the field of the coil, pushing the ring up. The accessory set includes a coil with a bulb that lights by induction when the coil is placed over the launcher core. It also includes several rings: one split aluminum ring that will not launch.