Conservation of angular momentum

Have you ever seen a spinning top or a merry-go-round? They move round and round and never seem to stop, right? That's because they have something called "angular momentum".

Angular momentum is like a special type of energy that makes things spin around and keeps them spinning. Just like how a ball that you throw keeps moving until it hits something, something that spins will keep spinning until something gets in the way. This is what we call the conservation of angular momentum.

Let me give you an example. Imagine you're spinning on a swivel chair. When you're not spinning, you're still, right? But when you start spinning, you've got angular momentum. Even if you stop pushing yourself, your chair will still keep spinning for a bit because the momentum you created keeps it going.

Now, imagine if you straighten your arms out while you're spinning on the chair - this will make you spin faster. Why? Because your arms are making your mass (that's how much matter you have in your body) more stretched out, so the same amount of momentum is spread out over a larger area, making you spin faster.

So, basically, conservation of angular momentum means that once an object starts spinning, it wants to keep spinning until something stops it. It also means that if you change the shape of an object while it is spinning, this will change how fast it's spinning. Cool, huh?