Seismic waves and the inside of the Earth sim
Drag seismometers round a cut-away Earth, read where the P- and S-waves start on each trace, map the shadow zones from your own readings, and switch the outer core to solid to see why it must be liquid.
General wave properties · covers the GCSE (mainly AQA), IGCSE and O-Level as examples only topic
What the sim shows
Model: a layered Earth (typical speeds, simplified layers; the crust drawn thicker); rays traced through thin shells with Snell's law, r sin i over v the same all along a ray; S-waves stop at the liquid outer core; only direct waves; travel times approximate. Slinky: each coil copies the grip's movement a little later. Nothing runs on its own.
- The cut face of the half-Earth model: the waves spread out across it from the epicentre
- A slinky shows the two kinds of wave: push–pull (P) and side to side (S)
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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