Ferromagnetic materials have

The correct answer is Option (1) → The large and positive value of susceptibility

The magnetic susceptibility \( \chi \) tells how strongly a material is magnetised in a field, \( M = \chi H \). In a ferromagnetic material the atomic dipoles line up in domains, and an applied field aligns the domains, giving a very strong magnetisation in the direction of the field.

    \( \displaystyle \chi \gg 1 \quad (\text{large and positive}) \)

Option (1) The large and positive value of susceptibility — Correct. Ferromagnets are strongly magnetised along the field, so \( \chi \) is large and positive (of the order of \( 10^{3} \) or more).

Option (2) The large and negative value of susceptibility — Incorrect. No material has a large negative susceptibility; the most negative value, \( \chi = -1 \), belongs to a superconductor.

Option (3) The small and negative value of susceptibility — Incorrect. A small negative susceptibility describes a diamagnetic material.

Option (4) Zero susceptibility — Incorrect. Zero susceptibility would mean no magnetisation at all, as in vacuum.

NCERT (2026-27):
Magnetic Properties of Materials – “The discussion in the previous section helps us to classify materials as diamagnetic, paramagnetic or ferromagnetic. In terms of the susceptibility χ, a material is diamagnetic if χ is negative, para- if χ is positive and small, and ferro- if χ is large and positive.”