Pressure in a Liquid
Pressure in a Liquid is a free interactive simulation for GCSE Physics (Edexcel IGCSE 4PH1) in which students vary the depth and the liquid to investigate how pressure in a liquid increases with depth and varies with liquid density. No login required — includes a worksheet and self-marking quiz.
Aim: To investigate how pressure in a liquid varies with depth.
P = ρgh
Pressure (Pa) = Density (kg/m³) × g (m/s²) × Depth (m)
Total pressure also includes atmospheric pressure (101 325 Pa)
Total pressure also includes atmospheric pressure (101 325 Pa)
Controls
Current Measurements
Atmospheric P
101 325 Pa
Liquid P (ρgh)
9 810 Pa
Total Pressure
111 135 Pa
Data Table
| # | Liquid | Depth (m) | ρ (kg/m³) | g (m/s²) | ρgh (Pa) | Total P (Pa) |
|---|---|---|---|---|---|---|
| No readings yet. | ||||||
- Select a liquid from the dropdown, e.g. Water.
- Set the Depth slider to 0 m, then increase it in steps of about 2 m, pressing Record Data Point at each depth. Record at least 5 readings.
- Change the liquid and repeat the same set of depths, recording a new set of readings.
- Repeat again for a third liquid so you can compare at least three liquids of different density.
- Plot a graph of Total Pressure against Depth for each liquid on the same axes.
- Compare your graphs — how does liquid density affect the gradient of the line?
- Think: why does pressure increase with depth, and why is the pressure non-zero even at zero depth?
Data point recorded!