PFE003: Magnets

Magnets: How do they fucking work?

I'm pretty sure it's magic. Or it could be this:

I'm pretty sure it's not this though.

Richard Feynman is credited as being many things and of having many skills. One such skill is his ability to explain things to anyone. Unfortunately, when it comes to magnets, he seems to be stuck and talks about the question "Why?" and other such things.

So how do magnets work?

First, what do we know? We know that sometimes two magnets attract each other, and that if you flip one they will repel each other. We also know that the force is really quite strong. One teeny magnet can lift a paper clip off the ground. But to do so, it has to overcome the gravitational force of the entire planet.

So we've seen that magnets are super strong. But more importantly, they seem to have a direction. If you flip a magnet around, it behaves in the opposite fashion next to other magnets. Moreover, a magnet can make certain metallic objects behave like magnets when they are near by, but they then lose this property as soon as you remove the original magnet.

But the nail and the upper paper clips look the same, so something must be changing in the paper clips at a very small level.

This is about as far as practical observations can take us. But first, let's talk about electricity. We all use electricity all the time, but rarely see the results of it first hand. One example when we do, is with balloons. Rub a balloon on your hair and it will stick to the side of your head. This attractive force comes from a difference in charge between the two.

The magnetic force is very closely tied to the electric force (actually, they're the same force). While we think of the electric force as an attraction (or repulsion) from the separation of charge, the magnetic force is an attraction or repulsion from the movement of charge.

Moving charge leads to a push or a pull? Okay, at this point you're going to have to take my word on it or pretend it's magic. I'm happy either way.

Once you've accepted this magnetic force, the reason that some things show it on a large scale and some don't has to do with how their very atoms behave. As the electrons move about the atoms, sometimes, across large portions of a metal, all the electrons are spinning in the same way. This allows the magnetic field to add up, and it adds up a lot, enough to be much more powerful than gravity from the entire earth!

That's magnets.