What is Pascal’s Principle?

Pascal’s Principle is all about how pressure moves through fluids, like water or oil.

Imagine you're squeezing a toothpaste tube from the top, the toothpaste squirts out from the bottom. That's kind of what Pascal’s Principle is like, but instead of toothpaste, we’re talking about liquids in containers with tubes attached.

If you push on one part of a fluid inside a container, that pressure travels to every other part of the fluid, and even up through any tubes connected to it. So if you have a big container full of water with little tubes sticking out, and you press down on one tube, the water will pop out from all the other tubes at the same time.

Think about a car lift in a garage. When you push down on a small pedal, it lifts up a heavy car. That’s because the pressure from your foot moves through the fluid and pushes up on the bigger part of the system, like magic, but actually science!

So Pascal’s Principle is just a fancy way of saying: push here, and everything else feels it.