**A vertical column of fluid exerts a pressure due to the column’s weight. The relationship between ****column height and fluid pressure at the bottom of the column is constant for any particular fluid ****(density) regardless of vessel width or shape.**

**This principle makes it possible to infer the height of liquid in a vessel by measuring the pressure ****generated at the bottom:**

**The mathematical relationship between liquid column height and pressure is as follows:**

**P = ρgh P = γh**

**Where,**

**P = Hydrostatic pressure**

**ρ = Mass density of fluid in kilograms per cubic meter (metric) or slugs per cubic foot (British)**

**g = Acceleration of gravity**

**γ =Weight density of fluid in newtons per cubic meter (metric) or pounds per cubic foot (British)**

**h = Height of vertical fluid column above point of pressure measurement**