Magnets are a pieces of iron or similar material that generates a magnetic field. Although this field is invisible to the human eye, it creates a force which helps pull other ferromagnetic materials towards it. That’s the reason why magnets will attract cobalt, nickel, steel and iron, among other compounds. They can repel or attract other magnets too.
How does a magnet work?
The way magnets work is rather complex. Every magnet has its south and north pole, with opposite poles being attracted to one another, while the same poles will always repel each other. Once you bring iron near a magnet, then the north-seeking poles in those atoms will line up in the same direction. The aligned atoms generate a magnetic field, which means the metal ends up attracted to the magnet.
There are temporary magnets, but there are also permanent ones. Temporary/soft magnets will generate a magnetic field when they are also in the presence of a magnetic field. Hard/permanent magnets however will create a magnetic field that doesn’t go away. And then we have electromagnets, which create magnetic fields solely when they have electricity going via the wire coils.
What kind of magnets are there?
You can find a multitude of magnet types, and these vary when it comes to strength and their own properties.
- Ceramic magnets are very common, and they have iron oxide within the ceramic composite. These are not very strong, and they are also called ferric magnets.
- Alnico magnets are made from cobalt, nickel and aluminum. These are quite a bit stronger when compared to the ceramic ones, however they lack rare earth metals with very powerful magnetic properties.
- Then you have neodymium magnets which have neodymium, as well as boron and iron.
- Samarium cobalt magnets are also powerful, they combine a rare earth compound named neodymium with cobalt.
- You can even find magnetic polymers.
When were magnets first discovered?
Magnets were a curiosity for scientists throughout human history. The first time magnets were mentioned was in 600 BCE. At that time, Lodestone was mentioned by Thales of Miletus in his work. The early lodestone was found in Magnesia in Greece, and that’s where the name Magnet comes from. However, that’s the first time we have written details about a magnet.
There were many other scientists and researchers that talked about or even worked with magnets over the years. Pliny the Elder who lived in the early AD in Rome documented a hill which attracted iron, a hill that was made of stone. At first, he thought that the powers of magnetite are actually generated by magic.
Items with magnetic properties were also found in Scandinavia and even Ancient China.
When was the first magnet made?
The first person that actually made a magnet was Willian Gilbert from Great Britain. He was a physician that created a magnet in 1600 after discovering that our planet itself was a magnet. At the same time, he identified the fact that you could make a magnet out of iron and you could also lose the properties of a magnet if you heated the iron.
Then we have Hans Christian Oersted who researched more about the relationship between magnetism and electricity.
Magnets have always been a fascinating topic for scientists and physicians throughout human history. Over the years, people started to learn how to use magnets, but also how to create new ones. In addition, electricity added yet another spin and new possibilities to the world of magnets. Which is why nowadays magnets have become very common and also extremely useful. People use them pretty much every day, yet the physics behind them is still fascinating even in modern times!