# How is it possible electromagnets keep a heavy maglev train levitating without forcing anything metallic to be flinged away?

I always wondered how it is possible to have electromagnets so strong that they keep a heavy maglev-train levitating without forcing anything metallic to be flinged away or to be pressed against the ceiling of the vehicle-cabin? And how come a person inside that train which has a pacemaker implanted is not affected? With a pacemaker someone cannot have a MRI scan but still ride a maglev train?

• Shaped pole pieces. Look at a horseshoe magnet - the field is especially strong right between the poles. You can design a magnet system to concentrate the field where you want it, and make sure there's very little elsewhere, like the passenger cabin. – Brian Drummond Feb 3 '17 at 15:51

Also it is important to note that magnets will pull or repel each other with much more strength that when they are close together than when they are far apart. For example dipole magnetic fields decay at a rate of $1/d^3$ which means that as the distance $d$ increases magnetic field gets weak very fast.