Hydraulics with two syringes, a jack and car brakes sim
Measure each plunger with digital calipers and work out its area, load the big syringe with slotted masses, push the small one with a newton-meter while the load rises and sinks, and find that F₁ over A₁ matches F₂ over A₂ in your own table; see the small plunger travel further, feel an air bubble make the push spongy and bleed it out, then work out the forces in a hydraulic jack and a car's brakes.
Pressure: pressure passed on through a liquid · covers the O-Level, IGCSE, GCSE topic
What the sim shows
Model. Pressure passed on equally through the water: F₁ over A₁ = F₂ over A₂, with ρ g h for the seals' heights and a rubbing friction on each seal (chosen, ±20 % stroke to stroke). Water does not squash; air follows pV = constant. Weight m g with g = 10 N/kg. Typical syringe sizes from memory. Nothing moves on its own: the plungers move only while you drag or press.
- The small plunger (you push it with the newton-meter)
- Syringes in clamps, water-filled tubing, bleed screw, masses, calipers, spare plungers
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.
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