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Magnetic globes

So you are trying to find a gift for that person who seems to already have everything? What to get them? Here is a great and unique product called a magnetic globe.

This gift is great for the college student, world traveler or just someone you know who really likes gadgets.

The question you must be asking yourself is: how does it work? Magnets are the key, and many a science teacher has used magnetic globes to demonstrate the unique powers of the magnet.

When you turn the globe on, electricity is sent to the magnet on the bottom and the top simultaneously, creating a magnetic field. In a sense the metal within the globe is being pulled in two directions at the same time.

To get more technical, as you look at a magnetic globe you will notice that at the top of the stand which holds the globe there is a large electromagnet made of iron. At the bottom of the stand is a sensor which measures the strength of the magnetic field. This sensor measures the amount of magnetic pull from the magnet in the bottom of the globe. By taking the combined measurement of the magnet in the bottom of the globe and the iron-core magnet in the top of the stand, the control circuit is able to determine how much power to apply to keep the globe positioned perfectly in the center.

One interesting experiment to try is to spin the globe while it is levitating. You will see that it can spin for approximately twenty minutes on the gyroscopic power you provided with the spin. The only thing that will eventually stop the globe is the actual drag of the air surrounding it and the minimal amount of drag produced when the control circuit is making millisecond adjustments.

Not only can a magnetic globe provide hours of geography pleasure, but you can also incorporate lessons about physics and natural alternative energy sources.