Statement check: In ferromagnetic materials (below Curie temperature), neighbouring permanent magnetic dipoles tend to align parallel within a domain. Is this statement correct?

Introduction / Context:
Ferromagnetism arises from exchange interactions that energetically favor parallel alignment of neighboring atomic moments. This leads to regions (domains) with spontaneous magnetization even without an external field. Recognizing domain-level alignment clarifies why ferromagnets can be strongly magnetized and exhibit hysteresis.

Given Data / Assumptions:

• Temperature below Curie temperature T_C.
• Crystalline ferromagnetic material with domain structure.
• No external field is necessary for spontaneous ordering inside a domain.

Concept / Approach:

Within a magnetic domain, exchange coupling minimizes energy when neighboring spins align parallel, producing a net magnetization. Different domains can orient differently to reduce magnetostatic energy, so a bulk specimen may have near-zero net magnetization until a field reorients domain walls.

Step-by-Step Solution:

Verification / Alternative check:

Magnetic imaging (e.g., Kerr microscopy) shows domain patterns with uniform magnetization directions separated by domain walls, validating parallel alignment within domains.

Why Other Options Are Wrong:

• False options ignore exchange interaction or conflate with paramagnetism, where alignment is weak and field-induced.

Common Pitfalls:

Confusing domain-level order (parallel inside domains) with macroscopic randomness (different domain orientations) that can yield a small net magnetization without an external field.

Final Answer:

True