In a moving coil galvanometer, the coil is wound over a metallic frame in order to
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → produce electromagnetic damping
When the coil turns in the magnetic field, the metallic frame also moves through the field, and eddy currents are induced in it. By Lenz's law these currents oppose the motion, so the coil comes to rest quickly at its final deflection instead of oscillating. This is electromagnetic damping.
Note: A similar question was also asked in CUET (UG) 2025 on 21-05-2025 (Slot 2).
Note: This question is from the pre-rationalised NCERT book (2022-23). The topic was removed from the latest NCERT book (2026-27), and it also appears to be out of the CUET 2026 syllabus.
NCERT (Pre-rationalised edition, 2022-23):
Eddy Currents – “… (ii) Electromagnetic damping: Certain galvanometers have a fixed core made of nonmagnetic metallic material. When the coil oscillates, the eddy currents generated in the core oppose the motion and bring the coil to rest quickly.”