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Gravity Fountain by Jesse and Chloe

We play in the water every chance we get. When we go to our favorite water park, we have a blast playing with the fountains. That got us thinking: what does it take to make a high-spraying fountain? We went to the Montshire Museum in Norwich, Vermont, to do some hands-on experimenting with water. They have an outdoor water exhibit called a rill, which is a little stream. Our goal: how can we make a gravity-fed water fountain that shoots 20 feet into the air?

What did we do?
While playing around at the rill, we discovered that the higher the water level above a fountain, the greater the water pressure of the fountain. We decided to try some backyard science to test this idea. Our gear was simple: plastic tubing, a plastic soda bottle (to use as a reservoir), and different size nozzles. We set up a little experiment, placing the nozzle 6 inches off the ground, at a 45 degree angle. Then we changed the height of the reservoir between 1,2,3, and 4 feet and recorded the length of the fountain spray for 3 tries at each height. Next we tried different size nozzles all with a reservoir set at 4 feet, to see how nozzle size affects length of the fountain spray.

What did we find out?
No doubt about it: We discovered that the higher the reservoir sat above the nozzle, the longer the fountain spray. When nozzle size was the variable, we learned that the larger the nozzle, the larger the longer the fountain spray. Then we took everything we knew about gravity fountains back to the Montshire to build the ultimate fountain.

What can you do?
  • Many fountains have their own pump systems to spray water into the air... how can you let gravity do the work for you? Think about experiments you could try if you had some water bottles, tubing, and nozzles available to you. Develop a plan for investigating which factors are most important for making the water shoot high in the air. Write your ideas in your notebook.
  • People have used falling water for centuries to do work for them. Take on the challenge of designing a contraption that uses falling water to complete a simple task. For example, come up with a device that uses falling water to pull an object across the table, or to lift a box into the air, or even to light a light bulb. Come up with as many different ways as you can to complete the task.
  • It seems like everybody is dropping mints into diet cola these days... why not make a science experiment out of it? What else makes a good fountain besides name-brand mints? Try granulated sugar, powdered sugar, salt, or other safe household items. Or try sugared sodas instead of diet. Organize your findings and develop a hypothesis about what features of diet soda seem to make it the preferred choice these days.
more resources
Go to the DFTV Boards, and tell us about your science investigation.
whiz quiz
What game was invented in 1931 by an unemployed architect?

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