I’ve been in a ‘magnet mood’ since I did my big post on the physics Nobel winners a week ago, and I thought it would be nice to show one of the most spectacular applications of magnetism – magnetic levitation (maglev) trains. China opened the first high-speed commercial maglev train line in the world in 2004 in Shanghai. I was there this January and my colleague set it up for us to take the train to the airport on departure.
In brief, magnetic levitation trains operate by just that – magnetic levitation. The train and the track are outfitted with magnets (both electromagnet and permanent magnet designs exist) and the train is either kept above the rail by repulsive forces or, in other designs, suspended below the rail by attractive forces. The typical train/rail distance is about a half an inch. The most obvious advantage of magnetic levitation is the absence of friction that would normally be present in wheeled vehicles.
Anyway, it’s quite a trip to ride it. The top speed on the Shanghai train is 431 km/h, which translates into 268 mph! I’ve put together a video of the experience, combining some a photo montage of the station and the city with video at the top speed. You get bonus points if you can recognize the background music I used!