Introduction to Magnetism
Magnetism is a fascinating property of materials that allows them to attract or repel other materials with similar properties.
You might have encountered magnets in everyday life, like refrigerator magnets, and noticed how they stick to certain objects.
This is because these objects are made from materials that have magnetic properties.
How Do Materials Become Magnetic
Magnetism in materials is a result of the behavior of tiny particles called electrons.
Electrons have an electric charge and they also spin like little tops.
This spinning of electrons creates a tiny magnetic field.
Normally, in most materials, these tiny magnetic fields are randomly oriented, meaning they point in different directions and cancel each other out.
As a result, the material as a whole doesn’t show any noticeable magnetic behavior.
Types of Magnetic Materials
Some materials, like iron, nickel, and cobalt, have a special ability.
When you bring a magnet close to them, their atomic magnets tend to align themselves with the external magnetic field.
This alignment creates a stronger and more organized magnetic field for the entire material.
As a result, these materials become magnets themselves and can stick to other magnets.
This is why you can pick up paper clips with a magnet.
Materials like aluminum and oxygen are paramagnetic.
They have tiny magnetic fields created by their electrons, but these fields are very weak and don’t tend to align with external magnets.
However, when you place a paramagnetic material in a magnetic field, it becomes a weak magnet itself, but it loses its magnetism when the external magnetic field is removed.
Diamagnetic materials, like water or wood, are the opposite of ferromagnetic.
They have tiny magnetic fields that tend to oppose external magnetic fields.
So, when you bring a magnet close, these materials become very slightly repelled by the magnet. The effect is weak and usually not noticeable in everyday situations.
How Temperature Affects Magnetism
Temperature can also influence magnetic behavior.
When you heat a ferromagnetic material, like iron, it becomes less magnetic because the heat gives the electrons more energy to move around, and this disrupts the alignment of their tiny magnetic fields.
This is why a piece of iron loses its magnetism when you heat it enough.
In A Nutshell
Magnetism in materials comes from the behavior of electrons and their tiny magnetic fields.
Some materials can become magnets themselves when exposed to external magnetic fields, while others respond weakly or oppose such fields.
Temperature can also affect magnetism, making materials less magnetic when heated.
Understanding these properties is key to many technological advancements in our daily lives.