Three samples are kept in the same weak external magnetic field: P is diamagnetic, Q is paramagnetic, and R is ferromagnetic below its Curie temperature. The temperature is increased considerably without a structural phase change. Which behaviour is most reasonable?
Options

Question

Three samples are kept in the same weak external magnetic field: P is diamagnetic, Q is paramagnetic, and R is ferromagnetic below its Curie temperature. The temperature is increased considerably without a structural phase change. Which behaviour is most reasonable?

Options

G1 Physics · Accepted Answer

Diamagnetic susceptibility arises from induced orbital effects and is generally very small and nearly temperature independent. For a Curie-law paramagnet, χₘ = C/T. Thus its susceptibility decreases as absolute temperature increases. Ferromagnetic order is also strongly temperature dependent and weakens as the Curie temperature is approached. Hence option B is correct.