What it shows
Pressure applied to a liquid in a closed system is passed on equally in every direction (Pascal’s law), so pushing one syringe moves its partner and lifts the arm.
This idea has a short entry only. For the science behind it, read the sentence above with your textbook and ask your teacher to explain the law or idea it shows, so you can describe it in your own words.
Materials
- 4 to 8 plastic syringes without needles
- Plastic tubing to fit
- Water, coloured so it is easy to see
- Cardboard or ice-cream sticks
- Nuts, bolts or split pins for joints
- A glue gun
Safety
For this project: An adult should handle the glue gun.
Never use mains electricity: power models with cells, batteries or a low-voltage adapter. Sharp and hot tools, flames and lab chemicals need an adult or your teacher beside you. Keep magnets, button cells and small parts away from young children, and wash your hands after making.
All the safety rulesHow to go about it
Numbered steps have not been written for this idea yet. Plan it with your teacher: sketch the design with measurements, build one part at a time, test each part, and write every observation with the date. The free ebooks below have step-by-step projects of the same kind.
Take it further
Fill one pair with air instead of water. Why does that joint feel springy?
Change one thing, measure what happens, and add a table or chart of your readings: that is what turns a model into your own investigation.
Free ebooks for this project
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