Purpose: To show the effect of induced current in conductors near the iron core of an electromagnet excited by 60 cycle A.C.

In this classic demonstration of electromagnetic induction, an aluminum ring is propelled straight up a maximum distance of 2 meters. The changing magnetic field from the AC powered 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. The induced magnetic field opposes the field of the coil, pushing the ring up.

References: