Which of the following statement is correct regarding the eddy current?

CONCEPT:

Eddy current:

• When a changing magnetic flux is applied to a bulk piece of conducting material then circulating currents called eddy currents are induced in the material.
• Because the resistance of the bulk conductor is usually low, eddy currents often have large magnitudes and heat up the conductor.
• These are circulating currents like eddies in the water.
• The experimental concept was given by Focault hence also named “Focault current”.
• The production of eddy currents in a metallic block leads to the loss of electric energy in the form of heat.
• Eddy currents are minimized by using laminations of metal to make a metal core. The laminations are separated by an insulating material like lacquer.
• Eddy currents are undesirable in the metallic cores of transformers, electric motors, and other such devices in which a coil is to be wound over a metallic core since they heat up the core and dissipate electrical energy in the form of heat.
• Eddy currents are used to advantage in certain applications like:
  1. Magnetic braking in trains
  2. Electromagnetic damping
  3. Induction furnace
  4. Electric power meters

EXPLANATION:

• Eddy currents are undesirable in the metallic cores of transformers, electric motors, and other such devices in which a coil is to be wound over a metallic core since they heat up the core and dissipate electrical energy in the form of heat.
• Eddy currents are used to advantage in certain applications like magnetic braking in trains, electromagnetic damping, induction furnace, electric power meters etc. Hence, option 2 is correct.