Hydrostatic Pressure Calculator (P = P₀ + ρgh)
Hydrostatic Pressure Calculator (P = P₀ + ρgh)
Hydrostatic pressure is the pressure exerted by a fluid at rest due to the weight of the fluid above a given point - it's why your ears pop when diving deeper into a pool, and why submarines need reinforced hulls to withstand deep-ocean pressure. Enter the fluid's density, the depth, and gravitational acceleration, and this calculator finds the gauge pressure (pressure from the fluid alone) and the absolute pressure (gauge pressure plus atmospheric pressure pushing down on the surface).
- P_gauge = ρ × g × h, so 10 m underwater in fresh water (ρ=1000 kg/m³), the gauge pressure is 1000 × 9.81 × 10 = 98,100 Pa, about 0.97 atmospheres.
- Absolute pressure adds atmospheric pressure on top, P_absolute = P₀ + P_gauge - at 10 m depth with standard atmospheric pressure (101,325 Pa), the absolute pressure is 101,325 + 98,100 = 199,425 Pa, almost double sea-level pressure.
- Pressure depends only on depth, fluid density, and gravity - not on the shape or size of the container, which is why a narrow tube and a wide swimming pool have the same pressure at the same depth.
How do I calculate water pressure at a given depth?
Use P_gauge = ρ × g × h, where ρ is the fluid density, g is gravity, and h is the depth. At 10 m in fresh water: P_gauge = 1000 × 9.81 × 10 = 98,100 Pa.
What is the difference between gauge and absolute pressure?
Gauge pressure measures only the pressure from the fluid above a point, while absolute pressure also includes the atmospheric pressure pressing down on the fluid's surface: P_absolute = P₀ + P_gauge.
Hydrostatic Pressure Calculator (P = P₀ + ρgh)
Hydrostatic pressure is the pressure exerted by a fluid at rest due to the weight of the fluid above a given point - it's why your ears pop when diving deeper into a pool, and why submarines need reinforced hulls to withstand deep-ocean pressure. Enter the fluid's density, the depth, and gravitational acceleration, and this calculator finds the gauge pressure (pressure from the fluid alone) and the absolute pressure (gauge pressure plus atmospheric pressure pushing down on the surface).
- P_gauge = ρ × g × h, so 10 m underwater in fresh water (ρ=1000 kg/m³), the gauge pressure is 1000 × 9.81 × 10 = 98,100 Pa, about 0.97 atmospheres.
- Absolute pressure adds atmospheric pressure on top, P_absolute = P₀ + P_gauge - at 10 m depth with standard atmospheric pressure (101,325 Pa), the absolute pressure is 101,325 + 98,100 = 199,425 Pa, almost double sea-level pressure.
- Pressure depends only on depth, fluid density, and gravity - not on the shape or size of the container, which is why a narrow tube and a wide swimming pool have the same pressure at the same depth.
How do I calculate water pressure at a given depth?
Use P_gauge = ρ × g × h, where ρ is the fluid density, g is gravity, and h is the depth. At 10 m in fresh water: P_gauge = 1000 × 9.81 × 10 = 98,100 Pa.
What is the difference between gauge and absolute pressure?
Gauge pressure measures only the pressure from the fluid above a point, while absolute pressure also includes the atmospheric pressure pressing down on the fluid's surface: P_absolute = P₀ + P_gauge.