Magnetic Levitation

The concept of “maglev” or magnetic levitation is becoming more commonly used in new technologies, especially in the arena of transportation. Unfortunately for the average reader, many articles on the subject are rather technical and make the idea seem mystically impossible to understand. At its heart, however, the theory of magnetic levitation is fairly basic and – once explained in simpler terms – pretty cool.

Magnetic Levitation Train in Shanghai, Photo: discopalace, Flickr

At the basic level, magnetic levitation starts with two magnets (you can do this experiment with refrigerator magnets). Magnets have two sides, called poles. When you put the opposite poles of two magnets together, they stick together. But when you try to put the same poles together, the two magnets repel each other – sometimes they flip over, or stick to the side of each other, but you can’t ever seem to put them together end to end. It’s this ability to repel other magnetic objects that is so useful.

Many technologies use this repulsive power in order to work. The problem with it, though, is that in order to be practical, you need to use electromagnets. An electromagnet can be made in a variety of ways, but the easiest way to make one is to wrap wire around an iron core (copper wire around a nail, for example), and run an electric current through it (by hooking it up to a battery). A magnet made this way will be just as effective – if not more so – at collecting paper clips as your refrigerator magnet is.

Chances are pretty high that you have some technology like this close at hand in your everyday life. Speakers, for example, use magnetic repulsion in order to create sound waves that are translated into music and voices. Speakers are not considered true maglev technology, however, because the magnets are secured into place (pseudo-levitation). The most common use of true magnetic levitation, however, is in transportation.

When used in transportation, magnetic levitation can create vehicles of phenomenal speed. Because there is no actual contact between a train and its track, a maglev train can travel at speeds upwards of 350 miles per hour. If the United States had a non-stop maglev train from one coast to the other, at that speed, it would only take nine hours to cross the country from Florida to Washington State. A trip from Seattle to Los Angeles would take just three hours.

The future of maglev technology is pretty bright. It’s currently being studied by NASA to see if it can be useful in launching ships and rockets into space. The US Department of Energy is studying magnetic levitation to see if it can be used to store energy more efficiently. Because magnetic levitation can affect materials that are not normally considered magnetic (like water, oil, and plastic), scientists in the United Kingdom are trying to figure out if a maglev mining system can be created that would essentially pull specific minerals out of the earth using magnetic forces. From the experiments of children in elementary school, to powering the world’s fastest trains, cool new innovations lurk on the horizon of magnetic levitation.