This exhibit displays induction by maintaining a magnetic field after the visitor turns off the current. Two horseshoes are placed together and coil around one is energized with current. The top horseshoe becomes am electromagnet and attracts the lower horseshoe. When the current is shut off, the lower horseshoe drops immediately if there is no secondary coil. If a secondary coil is present, the dying magnetic field of the primary creates a strong current in the secondary which makes the lower horseshoe into an electromagnet. Both horseshoes stick together until the energy in the secondary coil is dissapated by resistance and turned to heat at which time the bottom horseshoe drops.

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