Magnetic Properties Of Materials

A material is said to be paramagnetic if it has unpaired electrons in its atomic or molecular structure, which causes it to be attracted to an external magnetic field. Let's examine each option to determine which one is not paramagnetic:

Conclusively, the material that is not paramagnetic is Sodium Chloride.

Diamagnetic materials are repelled by magnetic fields because they create an induced magnetic moment in a direction opposite to the applied magnetic field. However, in a uniform magnetic field, the magnetic force on a diamagnetic object is zero because the net force depends on the gradient of the magnetic field. In a non-uniform field, the object would move toward the region of weaker field. Since the field is uniform here, the diamagnetic piece experiences no net force, and hence does not move.

Magnetic permeability is a property that indicates the ability of a material to conduct magnetic field lines. The magnetic permeability of a material is typically compared to the permeability of free space, denoted by . - Iron: It is a ferromagnetic material, meaning its magnetic permeability is much greater than that of free space. - Aluminium: It is a paramagnetic material, meaning its permeability is slightly greater than that of free space, but not as high as ferromagnetic materials. - Sodium: It is a paramagnetic material, and its magnetic permeability is slightly greater than that of free space, similar to aluminium. - Copper: It is a non-magnetic material, and its magnetic permeability is slightly less than that of free space, because it has a weak diamagnetic property. Hence, the correct answer is:

Materials that exhibit negative magnetic susceptibility are called diamagnetic materials. These materials are weakly repelled by magnetic fields. Their magnetic susceptibility (χ) is negative. Examples include bismuth, copper, and graphite.