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Maglev trains are the future of high speed trains.Maglev trains combines the benefits of airplanes with the benefits of trains to create“flying trains”.Maglev trains use electromagnetic techonology to allow trains to actually hover above the ground.With the friction of wheels on rails gone，a whole new era of high speed trains is possible.Tracks for maglev trains are different from those of conventional trains.They are elevated above ground，allowing everything else to go underneath it，and nothing will stand in the way of 300mile/h trains.
Maglev trains use the simple technology of magnets to raise the train of the ground，hence the name“maglev”.Everyone knows that if you put two magnets together in a certain way there will be a strong magnetic attraction and the two magents will clamp together.This is called“attraction”.If one of those magnets is fliped over then there will be a strong magnetic repulsion and the magnets will push each other apart.This is called“repulsion”.Now imagine a long line of magnets alternatly placed along a track，and a line of alternatly placed magnets on the bottom of the train.If these magnets are properly controlled the trains will be lifted off the ground by the magnetic repulsion or magnetic atraction.The power of the magnets can also be controlled to move the train foward，and fast.
How Maglev Trains Operate
Germany and Japan are good at maglev technology.They are using two different types of maglev trains.Germany is using the power of magnetic“attraction”，while Japan is mostly using magnetic“repulsion”.In Germany the bottom of maglev trains wrap around the track leaving only a 3/8 of an inch gap between the train and the track while in motion.In Japan，maglev trains have magnetic tracks underneath the trains as well as on the sides of the bottom part of the train.The magnets on the side of the track correspond with those on the side of the train while the magnets on the bottom of the track correspond with those underneath the train.The maglev trains in Japan have a 4 inch gap between the train and the track while in motion.When the trains in Japan slow down as they come into the station，wheels underneath the train reattach to the ground eventually bringing the train to a stop.
How Fast Can They Go？
Currently，the fastest maglev train in commercial service is in Shanghai，from Shanghai the to the New Shanghai Airport at Pudong.The highest speed achieved on the Shanghai track has been 501km/h，over a track length of 30km.Japan has a test track in Yamanashi prefecture where test trains have reached 581km/h，faster than wheeled trains.There is also a proposal for maglev lines through vacuum-filled tunnels，where the absence of air resistance would allow extremely high speeds，up to 6，000-8，000km/h according to some sources.Theoretically，these tunnels could be built deep enough to pass under oceans or to use gravity to assist the trains’ acceleration.This would likely be very expensive without major advances in tunnelling technology.
Are Maglev Trains Safe？
Maglev trains have been proven to be exceptionally safe，quiet，and fast.Beacause there’s no friction with the ground，maglev trains are much more quiet than trucks and automobiles.The only sound caused by the trains is the woosh as the train goes by from the air friction.Farmers in Germany who have trains running over their fields，when asked about how they feel about the trains running through their farm，replied“We don’t even know it’s there”.Cows don’t even lift their heads when trains come through at 250mile/h.Maglev trains are also almost accident free.They are above any obstacles on the ground and are enclosed in or around the track.Also the propelling system caused by the magnetic fields disallows trains to come to close to other trains on the track.
Another issue with maglev trains is whether the magnetic waves，or electromegnetic fields caused by the train will harm the passengers or people living along the lines.Studies have shown that the trains generateminimal magnetic fields，not enough to harm people around the track or any sensitive machinery.The tracks themselves do not generate any electromagnetic fields.The only time the magnetic waves are present is when the trains go by，but is only a short time，especially when they go by at 300 mile/h.The magnetic field inside the cabin of the trains is just barely higher than earth’s normal magnetic field.So maglev trains are very safe.
Questions for Discussion
1.How does maglev trains operate？
2.Are maglev trains safe？