Hydrostatic Paradox
A wide tank and a narrow tube filled to the same height push on their bases with the same pressure, even though one holds far more liquid. This simulation puts differently shaped vessels side by side so you can check the gauge readings against your intuition.
How to use this simulation
- Switch between cylindrical, conical and irregular vessels
- Change the fill height and the liquid density
- Read the pressure at the base of each
What to look for
- Equal heights give equal base pressures regardless of shape
- The volume of liquid can differ enormously with no effect on pressure
- Doubling the depth doubles the pressure exactly
The physics behind it
Hydrostatic pressure depends only on depth: P = ρgh. Neither the container's width nor the total weight of liquid enters the formula. The apparent paradox dissolves once you account for the force the sloping walls exert on the liquid, which carries the extra weight in a wide vessel and holds the liquid up in a narrow one.