Heron's fountain is a great project for a science fair, as it is simple to make and displays many of the basic principles of physics. This project shows how potential energy can provide power, using water and gravity, and air and compression. These are fundamental aspects of pneumatics and hydraulics and Heron's fountain also lets you have a bit of fun during the process.
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Heron's Fountain (Creative Commons) |
The great Greek inventor, Heron of Alexandria (sometimes called Hero) created this device as one of his wonderful ways of showing students how the underlying physical and mathematical principles worked. Historians are almost certain that Heron (c. 10 CE - c. 70 CE) taught at the great university of Alexandria, Egypt, and used many of his inventions as teaching aids.
You now have the chance to follow his example, by using this apparatus to show your classmates physics in action.
Heron's fountain was probably cast from bronze, at great expense, but we are going to make one from much simpler materials, easily found around the home or in a local hardware store.
A plastic basin
Two plastic soda bottles
Flexible plastic tubing, often used for aquariums
Two plastic jars with plastic lids
A stand for the basin
Silicone or some other waterproof sealant
A good explanation of how the Heron’s Fountain works. If you feel adventurous, you could try something like this for your science fair project!
The Pakistan Science Club shows how to make a Heron fountain. You can do this, too!
If you can get hold of glass flasks and rubber tubing, this is a great version of Heron’s fountain.
The water in the basin contains gravitational potential energy and, as it falls downwards, it uses the pneumatic pressure of the air in the air supply container to push the water in the upper, fountain supply container. Once the water drops below the level of the outlet tube in the fountain supply, the Heron fountain will stop.
This experiment has lots of variations and many different ways of building depending upon time and resources. If you make one, why not film it and upload it to YouTube - you never know; we might just decide to feature it here!
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Heron's Fountain (Creative Commons) |
At first glance, this appears to be a perpetual motion device; a machine that can keep running forever. However, this is not the case and, as the air supply flask fills with water, the jet of water from the nozzle will decrease in power and stop altogether. To restart the machine, you will need to empty this container and refill the fountain supply container with water.
The water in the basin contains gravitational potential energy and, as it falls downwards, it uses the pneumatic pressure of the air in the air supply container to push the water in the upper, fountain supply container. Once the water drops below the level of the outlet tube in the fountain supply, the Heron fountain will stop.
This experiment has lots of variations and many different ways of building depending upon time and resources. If you make one, why not film it and upload it to YouTube - you never know; we might just decide to feature it here!
Martyn Shuttleworth (Jan 15, 2011). Make Heron’s Fountain. Retrieved Dec 08, 2023 from Assisted Self-Help: https://app.assistertselvhjelp.no/en/herons-fountain