In 1835 Heinrich Lenz stated the law that now bears his name. An electric current induced by a changing magnetic field will flow such that it will create its own magnetic field that opposes the magnetic field that created it. These opposing fields occupying the same space at the same time result in a pair of forces. These forces are felt when you turn a generator and generate electricity. The more current you generate, the greater the force opposing you.
This have been use more commonly in the magnetic train in Japan or Bullet
Train it can run with maximum speeds of 240–3
20 km/h (150–200 mph).Japan was the first country to build dedicated railway lines for high-speed
travel. Because of the mountainous terrain, the existing network consisted of 1,067 mm (3 ft 6 in) narrow-gauge lines, which generally took indirect routes and could not be adapted to higher speeds. Consequently, Japan had a greater need for
new high-speed lines than countries where
auge or broad gauge rail system had more upgrade potential. Shinkansen trains are electric multiple unit style, offering high acceleration and deceleration, and reduced damage to the track because of lighter vehicles. The coaches are air-sealed to ensure stable air pressure when entering tunnels at high speed. the existing standard