Question

If the magnetic dipole moment of an atom of diamagnetic material, paramagnetic material and ferromagnetic material are denoted ny $\mu_d, \mu_p$ and $\mu_f$ respectively, then

• A. $\mu_{ p }=0$ and $\mu_{ f } \neq 0$
• B. $\mu_{ d } \equiv 0$ and $\mu_{ p }=0$
• C. $\mu_{ d } \neq 0$ and $\mu_{ f } \neq 0$
• D. $\mu_{ d }=0$ and $\mu_{ p } = 0$

Answer 1

Answer: (C)

Magnetic moment of ferromagnetic material $\mu_{ f }$ is non-zero always.
Under application of external magnetic field, the paramagnetic material has all the magnetic moments aligned giving off $\mu_{ p } \equiv 0$.

However the magnetic moments of atoms in diamagnetic material cancels out resulting in $\mu_{ d }=0$