Wolfram Demonstrations Project: "Electromagnetic Ring Toss"

This demonstration is modeled after a classic classroom demonstration. A conducting ring is placed atop an electromagnet, and a large pulse of current passes through the electromagnet. As seen in the lectures, readings, and demonstrations above, a current is induced in the conducting ring in a direction that opposes the formation of the magnetic field. As usual, this is to minimize the total energy of the system. The result is that the current in the ring generates a magnetic field with the opposite sign as that of the electromagnet. Opposed magnetic fields repel, so the ring launches into the air. Why does nothing happen when we use the split ring?