Physics of Maglev
It is known that a current carrying wire induces a magnetic field. A solenoid, which is a wire that has been coiled to form multiple circular loops, takes advantage of this property. A current-carrying solenoid creates a magnetic field that is almost uniform and has many practical applications. The magnetic field induced by a solenoid can be determined by the following equation:
where B = the magnetic field,
μ0 = 4π x 10-7 T·m/A,
N = number of loops,
L = length of the wire, and
I = current, A
It is by this principal of magnetic induction that creates the magnetic force needed to levitate this 50 ton train. This levitation eliminates all friction except for air resistance which helps the train reach speeds of up to 400 km/h.
Figure 1 shows the location of the propulsion coil that induces the magnetic field.
Figure 1.
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