Editing Pressure (section)

===Direction of liquid pressure===
An experimentally determined fact about liquid pressure is that it is exerted equally in all directions.<ref name="Hewitt">Hewitt 251 (2006){{full citation needed|date=July 2020}}</ref> If someone is submerged in water, no matter which way that person tilts their head, the person will feel the same amount of water pressure on their ears. Because a liquid can flow, this pressure is not only downward. Pressure is seen acting sideways when water spurts sideways from a leak in the side of an upright can. Pressure also acts upward, as demonstrated when someone tries to push a beach ball beneath the surface of the water. The bottom of a ball is pushed upward by water pressure ([[buoyancy]]).

When a liquid presses against a surface, there is a net force that is perpendicular to the surface. Although pressure does not have a specific direction, force does. A submerged triangular block has water forced against each point from many directions, but components of the force that are not perpendicular to the surface cancel each other out, leaving only a net perpendicular point.<ref name="Hewitt" /> This is why liquid particles' velocity only alters in a [[normal (geometry)|normal]] component after they are collided to the container's wall. Likewise, if the collision site is a hole, water spurting from the hole in a bucket initially exits the bucket in a direction at right angles to the surface of the bucket in which the hole is located. Then it curves downward due to gravity. If there are three holes in a bucket (top, bottom, and middle), then the force vectors perpendicular to the inner container surface will increase with increasing depth – that is, a greater pressure at the bottom makes it so that the bottom hole will shoot water out the farthest. The force exerted by a fluid on a smooth surface is always at right angles to the surface. The speed of liquid out of the hole is <math>\scriptstyle \sqrt{2gh}</math>, where ''h'' is the depth below the free surface.<ref name="Hewitt" /> As predicted by [[Torricelli's law]] this is the same speed the water (or anything else) would have if freely falling the same vertical distance ''h''.