The Levitron is commonly referred to as an anti-gravity device. Although this is not actually the case it is still an amazing toy. The operating principle of the Levitron is based upon what is known as spin stabilized magnetic levitation. The spinning top of a Levitron is a disk which is made up of strong permanent magnet material, in addition to plastic and brass. In the base of the Levitron there is a strong neodymium magnet. The top spins above this base. The magnets of the top and the base are oriented so that they repel each other when the top is in its upright spinning position.
Check out a video of a Levitron:
When the top spins inside the magnetic field of the base magnet, a gyroscopic effect creates stability, and as a result the top spins in a stationary position, as shown in the video. The gyroscopic effect is related to the angular momentum of the spinning top. As the top spins in the presence of the strong magnetic field (from the base magnet), stability is created due to a gyroscopic effect. This effect prevents the spinning top from turning over, and what happens instead is that the top spins and precesses about the vertical axis.
Eventually, after enough time passes, the spinning top slows down enough, due to air friction, such that it turns over and stops levitating. In other words, it falls.
Return to Science Toys page
Return to Real World Physics Problems home page
If you need one-on-one help with physics, get help from a Chegg Tutor! 30 minutes free for new users.