Humans have known about magnets for literally thousands of years. The ancient Greeks played around with them thousands of years ago and were the first to really start researching them. The word “Magnet” derives from Magnesia, the name of an Island where some magnetic rocks were once found. And while the ancient civilizations really had no way to explain how magnets worked, they found uses for them regardless.
One incredibly useful invention was the compass, which has a tendency to point (more or less) towards geographic north (Geographic north isn’t the same place as magnetic north!)
So, if I can pull your attention away from those great Intertops Poker Bonuses for a few moments, then using our big scientific brains of the modern world, how do we explain magnetism?
In order to understand how magnetism works, we have to understand how electricity works, since you can’t have one without the other. Electricity has also been known for thousands of years, and we can again credit the greeks for coming up with the word “Electron,” which is what they called amber.
How are amber and electricity connected, you may ask? The answer is static electricity. When you rub a piece of amber with certain kinds of clothes, you can generate static electricity.
Electricity is simply electrons moving from one location to another, in a massive conga line. Static electricity is generated by rubbing to things together, and the result either adds or removes electrons (not the amber).
Electrons, the modern kind, are small subatomic particles that are suspended around the nuclei of atoms (the protons and neutrons). You can think of them as orbiting the center, and although that’s not what’s really happening, it’s good enough just to understand the basics.
Electrons are negatively charged, protons are positively charged, and neutrons are neutral. It’s really easy to add or remove electrons from an atom (after all, rubbing two things together can get the job done). By contrast, protons and neutrons are nearly impossible to add or remove outside of nuclear bombs and particle colliders.
Nature likes to remain neutral. If there is a charge (positive or negative) electrons will move around to try and restore the neutrality. It’s like opening the door of a submarine underwater- there is an absence of water within the submarine, so water moves in to fill it.
In order to power your house, a difference in charge is created on purpose so that electrons will travel through your wires, and let you gain that sweet, sweet internet access. However, how does this connect to magnetism?
Unlike electrons, which are physical particles, magnetic fields are a result of disruptions in the electromagnetic spectrum. All charged particles, when moving, disrupt the electromagnetic spectrum. Since the most common charged particles you’ll find moving around are electrons, that’s the most common source of magnetic fields.
If you need an analogy, think of the magnetic field as sound from a highway, and the cars are electrons. Cars moving along the highway disrupt the air and generate sound that flows up and around the highway.
As a result, magnetic fields are everywhere, and the largest magnet on Earth is actually the Earth itself. Inside of the Earth, metals move via convection currents inside the Earth’s mantel and core. Since metals are conductors, their movement generates the Earth’s magnetic field.
Weirdly enough, that magnetic field around the Earth is probably why life on this planet was capable of surviving at all. Otherwise, we’d all be bombarded by cosmic radiation and… I’m getting off-topic.
So now, if you were to imagine a magnetic field, you can think of it as a line that flows out one end of the magnet and then loops around to enters the other end of the magnet. If you imagine this happening infinite times at different distances and angles, then you have a rough idea of the magnetic field.
Objects attracted to magnets, charged objects, and even other magnets interact with these “lines” to create these fascinating little objects we take for granted enough to slap onto our refrigerators.