Consider the two idealised systems (i) a parallel plate capacitor with large plates and small separation and (ii) a long solenoid of length $L \gg R$, radius of cross-section. In (i) $\mathbf{E}$ is ideally treated as a constant between plates and zero outside. In (ii) magnetic field is constant inside the solenoid and zero outside. These idealised assumptions, however, contradict fundamental laws as below

A paramagnetic sample shows a net magnetisation of $8 \mathrm{Am}^{-1}$ when placed in an external magnetic field of 0.6 T at a temperature of 4 K . When the same sample is placed in an external magnetic field of 0.2 T at a temperature of 16 K , the magnetisation will be

$S$ is the surface of a lump of magnetic material.

The primary origin (s) of magnetism lies in

A long solenoid has 1000 turns per metre and carries a current of 1 A . It has a soft iron core of $\alpha_r=1000$. The core is heated beyond the Curie temperature, $T_c$.