Question

what is the effect of eddy current in transformer​

Answer 1

The currents flowing in the core are called eddy currents. These currents produce heat, using up energy and so causing inefficiency. One way of minimising the effects of eddy currents is to make the core out of iron laminate. This is layers of iron separated by thin layers of an insulator such as varnish.

Answer 2

Explanation:

Eddy currents generate resistive losses that transform some forms of energy, such as kinetic energy, into heat. This Joule heating reduces efficiency of iron-core transformers and electric motors and other devices that use changing magnetic fields.