Attraction and Repulsion

Interaction Between Magnets

When two magnets are brought close to each other, they exert a force on one another. The nature of this force depends on which poles are facing each other.

The Fundamental Law of Magnetism

1. Like Poles Repel:

   • North Pole (N) $\leftrightarrow$ North Pole (N) = Repulsion (Push away)
   • South Pole (S) $\leftrightarrow$ South Pole (S) = Repulsion (Push away)

2. Unlike Poles Attract:

   • North Pole (N) $\rightarrow \leftarrow$ South Pole (S) = Attraction (Pull together)

Repulsion: The Sure Test

How do you distinguish between a magnet and a simple iron bar?

• Attraction is NOT a sure test: A magnet attracts another magnet (unlike poles) AND it also attracts a simple iron piece. So, if an object is attracted, it could be a magnet OR just iron.
• Repulsion IS a sure test: Repulsion only happens between two magnets (like poles). An iron bar will never be repelled by a magnet. Therefore, if an object is repelled, it must be a magnet.