Answer: 1.198 × 10⁶ A/m.
- A 2000 A/m
- B 1.198 × 10⁶ A/m
- C 599 A/m
- D 1.2 × 10³ A/m
Correct answer: B. 1.198 × 10⁶ A/m
Explanation: H = nI = 1000 × 2 = 2000 A/m, and magnetisation M = χH = 599 × 2000 ≈ 1.198 × 10⁶ A/m, illustrating the very large magnetisation typical of ferromagnetic cores.
Magnetic field lines form closed loops: outside the bar magnet they run from the N pole to the S pole; inside, they continue from S back to N, so the lines never start or end anywhere.
Concept context
Bar magnets, Earth's magnetism, and how different materials respond to an external magnetic field - diamagnetic, paramagnetic, and ferromagnetic behaviour.