This Archimedes’ screw is such a neat science lesson about simple machines! We use screws all the time to hold things together, but screws are also used to raise and lower things. In fact, a screw is actually an inclined plane (ramp) wrapped around a cylinder or a cone.
Archimedes was a Greek philosopher who lived from c. 287 – c. 212 BC. Some of the discoveries that he is known for are his work with levers, calculating an accurate estimate of pi, and using a screw to lift water. The Archimedes’ screw is still used today to pump liquids and even some solids.
Kids will enjoy this simple demonstration of how Archimedes’ screw is able to lift water. We found this experiment in our science book Exploring Creation with Chemistry and Physics (Amazon affiliate link), and I thought that the use of clear plastic tubing was genius!
For this demonstration, you will need:
- A bowl
- A glass
- A piece of PVC pipe – we used 1.5 inch diameter pipe, and our piece is about 14 inches long
- Clear plastic tubing, 1/4 inch inside diameter – you can find this at Lowe’s or Home Depot
- Clear packing tape
- Food coloring
The book suggested using a tin can, and that would definitely be a great option of you don’t have PVC pipe. We really enjoyed having a longer screw using the section of pipe, however.
Wrap the clear tubing around the pipe and secure it with clear packing tape. Duct tape would probably hold better (and for longer), but then you wouldn’t be able to see the water in the tube!
Put some water in your bowl and add a few drops of food coloring to make the water easier to see.
Then simply place your screw with the bottom end resting in the water. Put a glass under the top of the screw. Then start turning the pipe! The water will travel up the screw and drip out into the glass!
Note that the water stays in the underside of the tubing. As you turn the screw, it scoops up some water, then air, then water, etc. (This provides a side demonstration on the fact that air takes up space!) We tried raising the screw more upright so that the bottom of the tubing would always be under water, but that didn’t work.
Need mores science ideas?
- Learn about electricity with these Awesome Electricity Projects for Kids