Correct option is C
Explanation:
- Relative Permeability (μr) is a measure of how easily a material can become magnetized when exposed to an external magnetic field, relative to the vacuum (or free space). The permeability of free space (μ0) is a constant and serves as the baseline.
- Diamagnetic materials have a relative permeability slightly less than 1, which means they are repelled by magnetic fields. When an external magnetic field is applied to a diamagnetic material, it induces a small opposing magnetic field within the material, causing it to be repelled from the external magnetic field. Examples include bismuth and copper.
- Paramagnetic materials have a relative permeability slightly greater than 1, meaning they are weakly attracted to magnetic fields but do not retain magnetization once the external field is removed.
- Ferromagnetic materials have a relative permeability much greater than 1, meaning they are strongly attracted to magnetic fields and can retain magnetization after the external field is removed. Examples include iron, cobalt, and nickel.
- Non-magnetic materials generally refer to materials that are neither attracted nor repelled by magnetic fields and typically have a relative permeability close to 1.
Since diamagnetic materials have a relative permeability less than 1 (i.e., less than the permeability of free space), option (c) Diamagnetic is the correct answer.
