Eddy currents are loops of electrical current induced
within conductors by a changing magnetic field in the conductor
according to Faraday's law of induction. Eddy currents flow in closed loops
within conductors, in planes perpendicular to the magnetic field.
How are Eddy Currents Created?
They are induced by changing magnetic fields and flow in closed loops,
perpendicular to the plane of the magnetic field. They can be created when a
conductor is moving through a magnetic field, or when the magnetic field
surrounding a stationary conductor is varying i.e. anything which results in the
conductor experiencing a change in the intensity or direction of a magnetic
field can produce eddy currents.
Factors Influencing the Size of Eddy Currents
The size of the eddy current is proportional to the size of the magnetic
field, the area of the loop and the rate of change of magnetic flux, and
inversely proportional to the resistivity of the conductor.
Everyday applications where we benefit from Eddy currents
examples include electromagnetic braking, metal detectors, aluminum can
separation non-destructive testing,
Identification of metals , proximity and displacement sensors detection of coins
in vending machines and also for measurements of coating thickness.