Question

Define and describe magnetic dipole and magnetic susceptibility

Answer 1

Magnetic dipole_it is the product of dipole and magnetic length.

Answer 2

In electromagnetism, the magnetic susceptibility  is one measure of the magnetic properties of a material. The susceptibility indicates whether a material is attracted into or repelled out of a magnetic field, which in turn has implications for practical applications. Quantitative measures of the magnetic susceptibility also provide insights into the structure of materials, providing insight into bonding and energy levels.

If the magnetic susceptibility is greater than zero, the substance is said to be "paramagnetic"; the magnetization of the substance is higher than that of empty space. If the magnetic susceptibility is less than zero, the substance is "diamagnetic"; it tends to exclude a magnetic field from its interior. 

Mathematically it is the ratio of magnetizationI (magnetic moment per unit volume) to the applied magnetizing field intensity H.