Fluid Statics
Definition
The study of fluids at rest — pressure, buoyancy, and why dams are thicker at the bottom.
Technical definition
The branch of fluid mechanics for fluids in equilibrium: pressure varies with depth (P = P₀ + ρgh), Pascal's principle transmits pressure undiminished, and Archimedes' principle governs buoyancy. No shear stresses exist in a static fluid.
Example
A dam's wall is thickest at its base because hydrostatic pressure grows linearly with depth — the bottom bears the most force.
Common confusion
Fluid statics still involves forces — ‘static’ means the fluid is not flowing, not that nothing pushes. Pressure acts on every submerged surface even in perfectly still water.