The Curiosity Project
STEMingBoredom 28: home hydraulics
Air and water are two of the most common things on the planet, so common that we take them for granted. Now, obviously we know that water is a fluid, but did you know that in scientific terms, air is a fluid too?
Both can also be used to multiply force to move things and accomplish things. Take, for example, the drills that Formula One teams use to loosen and tighten wheel nuts in those incredibly quick tyre changes – they’re powered by compressed air.
Compressing air packs it together more tightly than normal, and it wants to go back to being less tightly packed – this is the energy that can be set free to do things.
But did you also know that water cannot be compressed? Its volume will always be its volume – you cannot get it into a smaller package.
How to do it:
Knowing this fact about water, we can use this lack of squeezing potential to move things – this is hydraulics.
A short length of tubing
An empty can
An empty plastic bottle
A heavy book
Attach the balloon to the tubing with the tape – make sure that the seal is really good, it will need to be watertight. Test it be putting the tube over the funnel end and pouring water through it. When it is proven to be watertight, drain the balloon and tube fully.
Cut the plastic bottle down so that it is just a little taller than the can – half a centimetre should be fine, it is so that the bottle guides the can.
Using a pencil or the scissors (carefully!), make a hole in the side of the bottle towards the bottom. Feed the pipe and balloon through so that the balloon is at the bottom of the bottle on the inside.
Place your heavy book on top of the bottle.
Finally, attach the funnel to the pipe and fill it with water. The balloon will fill, expanding and the power of the expansion due to the water will lift the book. That’s hydraulics!
If you have scales available, test what the heaviest weight you can move with your hydraulic ram.