Question

What is the reason for the magnetism in a magnet ?

• A. The orbital motion of the electrons
• B. The spin motion of the electrons
• C. The nuclear charge
• D. None of the above

Answer 1

The correct option is B The spin motion of the electrons

Electrons in most atoms exist in pairs, with each electron spinning in an opposite direction. Each spinning electron causes a magnetic field to form around it. In most materials, the magnetic field of one electron is cancelled by an opposite magnetic field produced by the other electron in the pair. The atoms in materials such as iron, cobalt and nickel have unpaired electrons, so they don't cancel the electrons' magnetic fields. As a result, each atom of these elements acts like a very small magnet. So, the magnetism in a magnet is mainly due to the spin motion of the electrons.