The Weak Nuclear Force

A brief introduction first. According to modern physics there are four elementary forces in nature: the gravitational force, the electromagnetic force, the strong nuclear force, and the weak nuclear force.

The gravitational force
This is the force that acts between all things that have mass. It keeps the earth orbiting around the sun, keeps your feet on the ground, and it is the one that makes you fall down the stairs. Most people are familiar with it.

The electromagnetic force
This one is responsible for chemical reactions, and a whole lot more (yes, electricity too). It also prevents stuff (i.e. matter) from falling to pieces by itself. Also, consider this: after you've fallen down the stairs (see gravitational force) and land on your feet (luckily), it is the force that stops you from falling to the center of the earth. You see, the gravitational force wants to pull you through the floor. It is the repulsion between the electrons in your feet and the electrons in the carpet that prevents this from happening. Good thing the electromagnetic force is so much stronger than the gravitational force, since there are far more atoms in the earth pulling on you than atoms in your feet resisting this.

The strong nuclear force
This one keeps atomic nuclei together. An atomic nucleus is composed of protons, which have a positive electric charge, and neutrons, which have no electric charge. Since the protons repel each other, there must be something that keeps the nucleus together. This something is the strong nuclear force. Think of it as a sort of glue. It's rather strong, but once the bond is broken, it does not work any more (the strong nuclear force works on very short distances only). Also, the enormous energies released in nuclear reactions are related to the strength of this force. Strong forces lead to high energies.

The weak nuclear force
This seems to be the Crazy Uncle Eddie in the family of fundamental forces. He's the kind of guy that gets drunk at family gatherings. It seems everyone is embarrassed to discuss him.
Seriously though, try to find some explanation of what the weak nuclear force is. You will probably find one of the the following explanations.
"The weak nuclear force is responsible for certain kinds of radioactive decay", or: "The weak nuclear force causes neutron decay", or "The weak nuclear force is responsible for Beta decay"
If you dig deeper you'll find something like: "It enables leptons and quarks to change into one another". I see. Also: "It's 1,000,000,000 times weaker than the strong force." Okay, that explains the name, I guess. Finally: "It's influence is limited to interaction within the atomic nucleus.". Alright, so?

Huh. Must be something so obvious that nobody can be bothered to explain what it is...

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