Liquid Displacement in U Tube
Pour two liquids that do not mix into a U-tube and they settle at different heights. This simulation lets you choose the densities and see the column heights adjust until the pressures balance at the bottom.
How to use this simulation
- Set the density of each liquid
- Add or remove liquid from either arm
- Measure the height of each column
What to look for
- The lighter liquid always stands higher
- The height ratio is the inverse of the density ratio
- Equal densities produce equal levels, whatever the tube's shape
The physics behind it
At the level where the two liquids meet, the pressure from each side must be equal, giving Οβhβ = Οβhβ. The less dense liquid therefore stands in a taller column. With a single liquid the densities are equal and the levels match, which is the principle behind every spirit level and water-level tool.