Electrostatics at work and as a hazard sim
Switch on a model smoke precipitator and watch the charged smoke stick to the earthed plates, charge a spray gun and see the paint wrap round an earthed can, and pump fuel into a tanker with and without its earthing strap to see why a spark can jump in the fuel vapour.
Static electricity: uses and dangers · covers the O-Level, GCSE topic
What the sim shows
Models with chosen values (beyond the syllabus). Precipitator: share of smoke caught = min(1, w L ÷ (u b)), with drift w = 2.5 mm/s per kV above 2 kV, plate height L = 150 mm, rising speed u = 40 mm/s and half-gap b = 30 mm: 0% at 2 kV, 31% at 3 kV, 94% at 5 kV. Spray: 41 droplets, each moving with the gun's fading air jet plus a drift toward the can that falls as 1 ÷ r (drag-dominated, no coasting). Refuelling: V = I R (1 − e^(−t/RC)) with I = 0.5 µA, C = 1000 pF, R = 10^12 Ω (tyres) or 10 Ω (strap); a spark at 6 kV across the 2 mm gap at the nozzle. Particles, droplets and charges are drawn larger than life.
- Precipitator and spray: the voltage knob on the EHT supply (drag it). Refuelling: the earthing strap's reel; drag its clip
- Earthed metal: the plates, the can, the earth point. Rubber tyres insulate the tanker from the ground
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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