Question

The magnetic susceptibility of an ideal diamagnetic substance is

• A. -1
• B. 0
• C. 1
• D. $\infty$

Answer 1

Answer: (A)

-1

Magnetic susceptibility $\chi$ is related to permeability $\mu$ by $\mu =1+4\pi {\chi }_m$.

For diamagnetic substances ${\chi }_m$ is negative and $\mu <1$ (negative). Ideal diamagnet should expel all magnetic field lines inside it i.e. ${\chi }_m<0$ or ${\chi }_m=-1$