Question

The core of any transformer is laminated so as to:
(A) reduce the energy loss due to eddy currents
(B) make it light weight
(C) make it robust and strong
(D) increase the secondary voltage

Answer 1

Hint
A transformer is a passive electrical device that transfers electrical energy from one electrical circuit to another, or multiple circuits. A varying current in any one coil of the transformer produces a varying magnetic flux in the transformer's core, which induces a varying electromotive force across any other coils wound around the same core.

Complete step by step answer
Electrical energy can be transferred between separate coils without a metallic (conductive) connection between the two circuits. Faraday's law of induction, discovered in 1831, describes the induced voltage effect in any coil due to a changing magnetic flux encircled by the coil.

Eddy currents are the loops of electrical current induced within conductors by a changing magnetic field in the conductor, due to Faraday's law of induction. Figure (a) shows eddy currents within solid iron transformer cores. Making the core out of thin laminations (figure b) parallel to the magnetic field with insulation between them reduces the eddy currents and thus also reduces the energy loss due to eddy currents.
Option (A) is correct.

Note
Transformers are usually used for increasing low AC voltages at high current (a step-up transformer) or decreasing high AC voltages at low current (a step-down transformer) in electric power applications, and for coupling the stages of signal processing circuits. Transformers can also be used for isolation, where the voltage in equals the voltage out, with separate coils not electrically bonded to one another.