[1] Regardless of approach, overcoming the Coulomb barrier is critical to achieving fusion ignition. The magnetic barrier apparatus demonstrates this process. A magnetic force levitates an upper magnet array above an identical lower array oriented in the opposite direction. Students determine the energy required to overcome a magnetic potential barrier by raising the upper array along the graduated shaft and letting it drop onto the lower array. Only by raising the upper array to a sufficient height is it possible to overcome the magnetic potential energy barrier and make the pair of magnetic arrays magnetically "fuse" together.