Gas pressure is what happens when tiny invisible particles inside something bump into each other and the walls, like a crowd at recess.
Imagine you're in a bounce house with your friends. The more people jump around, the harder they push against the sides of the bounce house. That’s gas pressure, it's like that crowd of friends jumping inside a big ball.
How gas pressure works
Think of a balloon. When you blow into it, you're putting lots of tiny air particles inside. These particles are moving super fast and bumping into each other and the sides of the balloon. The more you blow, the more particles there are, so they bump harder and make the balloon stretch.
If you let the air out, the number of particles goes down, so they don’t bump as much, that’s why the balloon gets smaller.
What makes gas pressure change
Sometimes it's like when you're playing tag in a small room. You’re all squished together and bumping around a lot, that's high pressure. If you run outside into a big field, there's more space, so you don’t bump as much, that’s low pressure.
Gas pressure is just the number of tiny particles moving inside something, and how hard they push!
Examples
- A balloon inflates because air molecules inside push against the balloon's surface.
- When you sip from a straw, the pressure difference between your mouth and the drink causes liquid to rise.
- A bicycle tire gets harder when you pump more air into it.