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 solenoid is given with 1000 turn per meter carrying a current of 1 ampere. The relative permeability of the soft iron core is =1000 and the Curie temperature is.


Formula used:


For a solenoid



where


His the magnetization of the core, n is the number of turns and I is the current flowing in the core.


Explanation:


Hence, to find the magnetization of the core we use the above formula,



The value of the magnetization and relative permeability is the same i.e. 1000. Therefore, at normal room temperature, a solenoid behaves like a ferromagnetic whereas if temperature is increased above Curie temperature it acts as a Paramagnetic Substance.


Thus, H remains Constant even after heating but the magnetic field falls extremely if heated past Curie temperature thereby a decrease in the susceptibility of the core and the material now acts as a Paramagnetic Substance.



Xm ferro is the susceptibility of the ferromagnetic substance and is the susceptibility of a paramagnetic substance. Therefore, the magnetization of the core diminishes by a factor of

1