What makes things move and what makes them stop?
Stubborn Things
What makes things move and what makes them stop?
Look around you. A rolling ball, a closing door, a sleeping cat that absolutely refuses to budge. Some things zoom, some things stop, and some things just sit there being lazy. So what's the secret rule behind all of it? Let's go find out.
Here's the big surprise: things don't actually WANT to move. And once they're moving, they don't want to stop, either. Whatever a thing is doing, it would happily keep doing forever — unless something comes along and bosses it around. This stubborn streak has a fancy name: inertia. Think of it as a thing's deep love of "leave me alone."
