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The core used in transformers and other electromagnetic device is laminated to

The core used in transformers and other electromagnetic device is laminated to Correct Answer Reduce eddy current losses in the core

CONCEPT:

  • Transformer: An electrical device that is used to transfer electrical energy from one electrical circuit to another is called a transformer.
  • Eddy Current: When a changing magnetic flux is applied to a bulk piece of conducting material then circulating currents is 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 the conductor.
    • Due to the heating of the conductor, there is a loss in energy. This loss is called eddy current loss.


EXPLANATION:

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  • The core is laminated to reduce eddy current to a minimum as they interfere with the efficient transfer of energy from the primary coil to the secondary one. So option 4 is correct.
  • The eddy currents cause energy to be lost from the transformer as they heat up the core - meaning that electrical energy is being wasted as unwanted heat energy.

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