Pressure = force ÷ area: a brick on sand sim
Turn a real brick onto each of its three faces in a tray of sand and add 1 kg masses, record the pressure each time, and plot pressure against 1/area to see the same force give more pressure on a smaller area.
Pressure · covers the O-Level, IGCSE, GCSE topic
What the sim shows
Pressure is the force on each square metre: p = F ÷ A, in pascals (1 Pa = 1 N/m²). The brick is a standard 215 mm × 102.5 mm × 65 mm brick of mass 2.5 kg, so its weight is 2.5 kg × 10 N/kg = 25 N (g = 10 N/kg). Its faces have areas of 220.4 cm², 139.8 cm² and 66.6 cm², so the same 25 N gives 1134 Pa, 1789 Pa and 3752 Pa: the smaller the area, the bigger the pressure. Each 1 kg mass adds 10 N. How far the brick sinks is only an illustration that rises with pressure (1.6 mm for every 1000 Pa); real sand does not behave like a simple spring.
- Brick: drag it sideways to turn it onto its next face
- 1 kg slotted masses: drag one onto the brick to add 10 N
- Sand: the brick sinks further where the pressure is higher
Use it in your lessons
- Try it here: anyone can unlock 2 figures free, and a free account unlocks up to 5. Runs on a laptop, a Chromebook or a phone; nothing to install.
- Present it and share student links with the teacher plan, from US$5 a month, billed yearly.
- Put it on your own website or LMS for US$9, paid once, or every sim from US$29 a month.
Free guide: 12 practicals as sims, and how to run one in a lesson →
Need a version for your exact set-up? Have one made: US$49 a figure in an order of 5.
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