Magnetic Materials | MCQs

Explanation

The magnetic materials include cobalt, iron, and nickel.

Plastic cannot be magnetized nor can it be attracted to a magnet.

Explanation

Copper is a non-magnetic material, meaning it does not exhibit magnetic properties.

Cobalt, Iron, and Nickel are magnetic materials, as they can be magnetized and attract magnets.

Explanation

Fe3O4 occurs as a mineral with a chemical name Iron (II, III) oxide.

It is also known as Magnetite or Magnetic oxide.

Explanation

In the double-touch method, opposite poles (north and south) of two magnets are rubbed on the material in opposite directions to magnetize it effectively.

This helps align more magnetic domains inside the material.

Explanation

Iron magnets are temporary because they lose magnetism quickly when the external magnetic field is removed.

Steel magnets retain their magnetism for a long time, making them permanent magnets.

Explanation

Explanation

Ferromagnetic materials are those that can be magnetized and retain their magnetization even after the external magnetic field is removed.

These materials have a high magnetic permeability and strong interactions between magnetic moments, which align in the same direction.

Explanation

Explanation

Ferromagnetic materials are those that can retain their magnetization even after an external magnetic field is removed.

They are strongly attracted to magnets. Iron, nickel, and cobalt are all ferromagnetic materials.

Barium, on the other hand, is not ferromagnetic

It is classified as a diamagnetic material, meaning it weakly repels magnetic fields. 

Explanation

• Aluminum is a non-ferrous metal.
• It is not capable of being magnetized or attracting magnets.