Correct option is B
Cobalt is an example of a ferromagnetic material. Ferromagnetic materials exhibit strong magnetic properties and can be magnetized to form permanent magnets. These materials have unpaired electrons, and their magnetic moments align parallel to each other in the presence of a magnetic field, producing a strong overall magnetic field.
Explanation of Options:
1. Non-magnetic:
Materials that do not exhibit any magnetic properties. Examples include wood and plastic.
Cobalt does not belong to this category.
2. Ferromagnetic:
Materials like cobalt, iron, and nickel are ferromagnetic.
They have a strong attraction to magnetic fields and can retain their magnetization even after the external magnetic field is removed.
3. Diamagnetic:
Diamagnetic materials are weakly repelled by a magnetic field. Examples include copper and gold.
Cobalt does not exhibit diamagnetic behavior.
4. Paramagnetic:
Paramagnetic materials are weakly attracted to magnetic fields, and this attraction disappears when the field is removed. Examples include aluminum and platinum.
