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Levitation. Maglev trains have no contacts with the rails while they move forward. They are levitated on the guide-way with the help of magnetic forces. Levitation is the process by which an object is suspended against gravity in a stable position without any physical contact.
From the middle of the twentieth century, the engineers are working on the maglev train concept. In 1968, James Powell, a researcher at Brookhaven National Lab, thought of using maglev trains (derived from magnetic levitation).