Question

A long solenoid has 1000 turns per metre and carries a current of 1A. It has a soft iron core of ${\mu }_T$-1000. The core is heated beyond the Curie temperature, $T_C$.

• A. The H field in the solenoid is (nearly) unchanged but the B field decreases drastically.
• B. The H and B fields in the solenoid are nearly unchanged.
• C. The magnetization in the core reverses direction.
• D. The magnetization in the core increases by a factor of about ${10}^8$

Answer 1

Answer: (A), (D)

The correct options are
A The H field in the solenoid is (nearly) unchanged but the B field decreases drastically.
D The magnetization in the core increases by a factor of about ${10}^8$