What is the magnetic susceptibility of a medium if its relative permeability is $0.85$?

What is the magnetisation of a substance?

Oersted is a unit of

The susceptibility of $Al$ is $2 \times 10^{-5}$. The percent increase in the magnetic field when the space within a current-carrying toroid is filled with $Al$ is:

The relation between total magnetic field $(B)$,magnetic intensity $(H)$,permeability of free space $(\mu_{0})$,and magnetic susceptibility $(\chi)$ is:

An iron rod of susceptibility $599$ is subjected to a magnetising field of $1200 \, A m^{-1}$. The permeability of the material of the rod is $(\mu_{0} = 4 \pi \times 10^{-7} \, T m A^{-1})$.