# Specific meaning of Pascal's principle

I'm having trouble understanding the Pascal's principle. I don't wanna know about the proof or derivation. But just what it means.

The pressure applied to any part of the enclosed liquid will be transmitted equally in all directions through the liquid

As far as I know, the pressure in an enclosed liquid is not same throughout. The deeper you go the more the pressure. So what does the Pascal's principle mean when you apply an external force to that liquid(or fluid)?

Assume that the pressure caused by the applied force is x pa.

Does the Pascal's principle state that after this force is applied the pressure everywhere in the fluid will be x Pa? Or that it will INCREASE by x Pa?

Let's say that, before applying the force, at some point of the liquid the pressure was k Pa. After applying the force, will the pressure at that point(and every other point of the fluid) be x Pa or k+x Pa?

## 2 Answers

Pascal's principle means that when you apply a pressure to any part of an enclosed liquid, all pressures within that liquid will increase by that amount. Obviously, the deeper you go into the liquid, the higher the pressure becomes, but the pressure increase from an applied pressure is the same everywhere in the liquid.

• Thanks,mate. Helped a lot. At first i thought this,too but I asked someone else and he said that it wouldn’t increase but it'd be the same throughout. That's why I asked even though tbh it was pretty basic. Commented Sep 27, 2021 at 15:52

My understanding of Pascal's principal differs from that of @David White. It has to do with the direction that the pressure acts at a point in a fluid. If you had a tiny imaginary element of surface area dA oriented in any direction at point within a fluid, the force on the surface pdA would be independent of the orientation (i.e., the same in all directions). Thus, for example, the pressure in the horizontal direction at a point in the fluid is the same as the pressure in the vertical direction.