Hydrostatic pressure
Static fluid pressure rises with depth under gravity.
Key knowledge
In a static fluid of uniform density under uniform gravity, pressure at vertical depth h below a reference level is p = p₀ + ρgh, where p₀ is pressure at that level.
Values and equations
p = p₀ + ρgh
- p
- Pressure at the lower level Pa
- p₀
- Pressure at the reference level Pa
- ρ
- Uniform fluid mass density kg m⁻³
- g
- Magnitude of uniform gravitational acceleration m s⁻²
- h
- Downward vertical depth from the reference level m
Conditions and scope
- The fluid is at rest in the chosen inertial frame; ρ and g are constant over the depth considered.
- h is a downward vertical depth; p₀ need not be atmospheric pressure.
- Variable density, acceleration of the container and moving-fluid pressure require a different treatment.
Sources · 2
References
Sources retain their recorded scope. A source link alone does not establish verification of every statement.
Evidence and review
OpenStax 14.1, equation 14.4 and static-fluid force balance; constant-density restriction contrasted with the atmosphere.
2026-10-10 · Uniform-density hydrostatic pressure difference only; no general flowing-fluid pressure law is asserted.
Foundational review
2026-10-10 · Fresh primary-source inspection of the complete compact record, including every statement, equation, quantity and material condition, followed by independent AI editorial review. This check does not certify all linked lessons or every passage of every cited publication.
Sources from other places
Agreement within this scope
Static uniform-density fluid under constant gravity has downward pressure increase ρgh.
The upper reference pressure can be chosen generally; an open surface is the atmospheric special case.
National Council of Educational Research and Training (NCERT)
- Mechanical Properties of Fluids · Physics (2026–27 reprint) IndiaEnglish
9.2.2 Variation of pressure with depth, equations9.5–9.7, pp182–183
- Mechanical Properties of Fluids · Physics (2026–27 reprint)
Entry details
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- physics-hydrostatic-pressure
- Revision
- core.1
- Structured reference record
- Essential core · first collection · University core expansion