An object that produces a weak repulsive force in the presence of a strong magnetic field is called what?

An object that produces a weak repulsive force in the presence of a strong magnetic field is identified as diamagnetic. This characteristic arises from the material's tendency to generate an induced magnetic field in opposition to the applied magnetic field. In diamagnetic materials, the electrons experience a change in motion in the presence of a magnetic field, which leads to this repulsion effect. Unlike ferromagnetic and paramagnetic materials, which exhibit attraction to magnetic fields, diamagnetic materials will be weakly repulsed when exposed to such fields.

Diamagnets demonstrate this behavior regardless of temperature and do not retain any magnetization in the absence of an external magnetic field. This distinct trait is why they are classified in this manner, as opposed to the other types of materials listed in the question.