Question:
A long solenoid has 1000 turns per meter and carries a current of 1 A. It has a soft iron core of μr = 1000. The core is heated beyond the Curie temperature Tc
(a) the H field in the solenoid is unchanged but the B field decreases drastically
(b) the H and B fields in the solenoid are nearly unchanged
(c) the magnetisation in the core reverses direction
(d) the magnetisation in the core diminishes by a factor of about 108
Solution:
(a) the H field in the solenoid is unchanged but the B field decreases drastically
(d) the magnetisation in the core diminishes by a factor of about 108