# PRESSURE IN FLUIDS

All liquids and gases are fluids. A solid exerts pressure on a surface due to its weight.
fluids have weight, and they also exert pressure on the base and walls of the container in which they are enclosed. Pressure exerted in any confined mass of fluid is transmitted undiminished in all directions.

Calculation of fluid pressure

Pfluid = P + ρgh
where,
P = Pressure at the reference point

Pfluid = Pressure at a point in a fluid

ρ = Density of the fluid

g = Acceleration due to gravity (considering earth g = 9.8 m/s2 )

h = Height from the reference point

The density of a fluid may be estimated by dividing its mass by the volume of fluid taken into account.

ρ = m/V

where,

m = Mass of the fluid

V = Volume of fluid considered

If the fluid is subject to atmospheric pressure, then the total pressure on the system is given by

Pfluid = Po + hρg

where,

Po = Atmospheric pressure

Conditions for the Consideration of Fluid Pressure:

We examine fluid pressure in two scenarios:

open circumstances or open channel flow
closed conduit or in a closed state
Hydrostatic pressure, also referred to as static fluid pressure, is the fluid pressure that is listed above. Because the pressure produced by fluid movement may be considered to be minimal, it is only taken into account here in relation to the fluid’s depth. The volume, mass, total surface area, and container type of the liquid have no bearing on the static fluid pressure.

Factors that affect Fluid Pressure

The pressure of a fluid is affected by two factors. The fluid’s depth and density are these two components.

Depth of the fluid: As the fluid’s depth increases, so does its pressure.
The density of the fluid: Denser fluids like water impose higher pressure compared to lighter fluids like air.