Start by turning the ring flinger on and setting the switch to steady. This will induce a current on the coils of wire on the ring flinger. This in turn will create a magnetic field for the ring flinger. Show students that the magnetic field exists by moving the compass needle close to the charged pillar. The needle should move. Switch the ring flinger off. Explain to students how a completed circular ring allows the current to travel around the ring. Demonstrate this by placing a completed ring on the now uncharged ring flinger pillar. Turn the switch of the ring flinger to impulse and show how the ring flies into the air due to the ring flinging upward due to the direction of the field. Reinforce this idea again by turning the ring flinger to steady and trying to put the ring back on the pillar. Repeat these steps with the incomplete ring to show how the magnetic field won’t act on the ring. This is because the eddy currents escape through the slit in the ring. Now demonstrate the differences in the “fling” with differing sizes of rings as well as different temperatures of the rings by using rings soaked in liquid nitrogen.

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