Jumping Rings
From UO Physics Demonstration Catalog
Return to Inductance
Description:
An AC solenoid with a moveable iron core. Turn the AC current and the changing produced 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, there is no induced magnetic field in the ring. . There is also a small coil with a light bulb to show that the AC changing magnetic field from main solenoid can be picked up by a coil and light a bulb. A good introduction to transformers and even wireless communication. The light bulb can be placed in a beaker of wire to also show there is no electrical connection to the bulb.
Location:
- Solenoid: Shelf J-3
- Accessories: Drawer 74