The core of a transformer is laminated to:

The correct answer is Option (2) → reduce energy loss

The changing flux in a transformer core also induces currents in the iron itself, called eddy currents, and these heat the core (an \( I^{2}R \) loss). A core built of thin sheets insulated from one another breaks up the paths of these currents into small, high-resistance loops, so the eddy currents and the heat they produce become much smaller.

Why the other options are incorrect

• Option (1) increase energy loss — Incorrect. This is the opposite of the purpose of lamination.

• Option (3) increase magnetic flux — Incorrect. The flux in the core is fixed by the winding current and the core material; thin sheets of the same iron do not increase it.

• Option (4) increase resistance — Incorrect. Lamination does raise the resistance offered to eddy currents, but that is only the means; what the designer wants is the reduction of energy loss.

Note: A similar question was also asked in CUET (UG) 2026 on 30-05-2026 (Slot 2), and in CUET (UG) 2025 on 13-05-2025 (Slot 1).

NCERT (2026-27):
Transformers – “… (iii) Eddy currents: The alternating magnetic flux induces eddy currents in the iron core and causes heating. The effect is reduced by using a laminated core.”