Fluid pressure

Fluid pressure can be defined as the pressure on a given object on the surface of a closed container or in the fluid. Gravity, acceleration, or forces outside the container, are the factors that cause the pressure.

Pressure is a scalar quantity that is stated as force per unit area. Here force acts in the direction perpendicular to the surface. Depending on the context of use, there are a number of units in which pressure can be measured.

Pressure = Force/ Area

P = F / A

Where

P = Pressure

F = Force

A = Area

Unit of pressure is N/m² or Pa (Pascal).

Hydrostatic pressure can be stated as the pressure exerted by a fluid at equilibrium at a given point within the fluid, due to the force of gravity. Hydrostatic pressure is proportional to the depth measured from the surface as the weight of the fluid increases with a downward force applied.

The fluid pressure can be caused by gravity, acceleration, or forces when in a closed container. Consider a container filled with water or any other fluid along with a ball in the bottom. Now consider the ball from the top of the container. There is pressure exerted by the layer of water acting on the ball. As we move down from the top of the container to the bottom, the pressure exerted by the top layer on the ball adds up. This phenomenon is responsible for more pressure at the bottom of the container.

As we can see in the above figure a ball is completely submerged in a fluid. Here force applied by the fluid on the ball equals to Hydrostatic pressure. Top Layer of the fluid exerts the most pressure on the ball. When we move the ball upside, the pressure applied by the top layer starts to reduce.