Jumping Rings

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Description:

An AC solenoid with a moveable iron core. Turn on the AC current, the changing magnetic field will induce a current in the ring that produces an Out of Phase magnetic field in the center of the ring which will send the ring flying off the iron core. Cool the aluminum ring in Liquid Nitrogen, and the ring will fly much higher (hitting the ceiling in Room 100!) since the resistance of the ring is much less, and this creates a higher current and a larger induced magnetic field.

There are heavy and light rings available. One ring is cut to show that if no current is induced in the ring, there is no induced magnetic field in the ring. There is also a ring with a light bulb attached across the diameter of the ring. This is placed atop the iron core to show that the AC changing magnetic field from main solenoid can be picked up by a coil and light a bulb. As and added dramatic effect, this ring (with bulb) can be submerged in water. A good introduction to transformers and even wireless communication.

Location:

• Solenoid: Shelf J-3
• Accessories: Drawer 74