Calculation
p = ρ·g·h
Hydrostatic pressure depends only on liquid-column height and density, not on the vessel's shape or cross-section.
Dubbel Mechanik B 5 Hydrostatik: dp/dz = ρ·g, p = ρ·g·z (+ p0)
Hydrostatic pressure of a liquid column
Hydrostatic pressure depends only on liquid-column height and density, not on the vessel's shape or cross-section.
MINTSI
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Result
Select a target and calculate.
Understand the inputs
- Hydrostatic pressure p — Additional pressure at the considered point relative to the liquid surface, caused solely by column height.
- Liquid density ρ — Density of the still liquid.
- Gravitational acceleration g — Local gravitational acceleration, about 9.81 m/s² near sea level.
- Column height h — Vertical distance between the liquid surface and the considered point.
Example
ρ=1,000 kg/m³, g=9.81 m/s² and h=10 m give p≈0.981 bar (98,066 Pa).
Assumptions and limits
Still, incompressible liquid with density constant over height; ambient air pressure at the surface is not included (result is the gauge pressure from the column alone).
Understand Hydrostatic pressure of a liquid column
This calculator determines the pressure at the base of a still liquid column, the basic physical principle behind manometers, dive-depth ratings and vessel design.
What does this quantity describe?
In a still liquid, pressure grows linearly with depth: p=ρ·g·h. The pressure increase depends only on the column's density and height, not on the vessel's shape (the hydrostatic paradox).
Formula and variables
p = ρ·g·h
p = ρ·g·h
| Symbol / input | Meaning |
|---|---|
| Hydrostatic pressure p | Additional pressure at the considered point relative to the liquid surface, caused solely by column height. |
| Liquid density ρ | Density of the still liquid. |
| Gravitational acceleration g | Local gravitational acceleration, about 9.81 m/s² near sea level. |
| Column height h | Vertical distance between the liquid surface and the considered point. |
Choose the inputs correctly
ρ is the liquid's density, g gravitational acceleration, h the height of the liquid column above the considered point.
How to use the calculator
Take ρ from material tables (water 1,000 kg/m³), use h as the actual fill height or dive depth.
Worked example
ρ=1,000 kg/m³, g=9.81 m/s² and h=10 m give p≈0.981 bar (98,066 Pa).
Understand the result and units
The computed pressure is the gauge pressure relative to the liquid surface; actual absolute pressure follows only after adding the ambient pressure acting there.
ρ is a density, g an acceleration, h a length. p is output as a pressure.
Typical applications
Sizing vessel walls and submersible pumps, estimating dive-depth pressures, and a basis for interpreting manometer readings.
Assumptions, limits and common mistakes
Still, incompressible liquid with density constant over height; ambient air pressure at the surface is not included, nor is temperature's effect on density or moving liquids.
Common mistake: Do not confuse the result with absolute pressure; for absolute pressure, the air pressure at the surface must still be added.
Frequently asked questions
What is “Hydrostatic pressure of a liquid column” used for?
Sizing vessel walls and submersible pumps, estimating dive-depth pressures, and a basis for interpreting manometer readings.
Where do the input values come from?
ρ is the liquid's density, g gravitational acceleration, h the height of the liquid column above the considered point.
What does the result not cover?
Still, incompressible liquid with density constant over height; ambient air pressure at the surface is not included, nor is temperature's effect on density or moving liquids.