Maglev technology has been around for years as the propulsion method behind certain European and Asian trains, and basically involves using the Physics 101 properties of magnetic attraction and repulsion to provide an object with momentum.

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The coil is suspended in an external magnetic field and the current running through it adjusted so that the attraction between the two magnets balances the gravitational force on the suspended mass.

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London's magnetic attraction is also increasing, relative to the rest of Britain.

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