# Eternal looping water tap

If i have a container like this (filled full with water):

and I unplugged the small tap, would the water pressure be big enough to blast the water to the right side of the container and cause an infinite flow of water like this?:

If you have a $$3D$$ printer, can you please print this .obj file, fill it with water (plug the little tap with your thumb until full), try it, and tell me if it works? It would be super appreciated, as well if someone with Physics and math experience who could use the dimensions of the figure in the images above to figure out if it would work or if this was even possible.

• If it's perpetual motion that generates power, it won't work. The highest the water jet can possibly go is to the height of the water in the side chambers. – S. McGrew Jun 23 '20 at 1:21
• In general, when you have an idea for perpetual motion, search "perpetual motion" on the internet. You will probably find your idea along with a detailed explanation of why it can't possibly work. The laws of physics are called "laws" for good reason: Nature doesn't violate them. – S. McGrew Jun 23 '20 at 1:25
• coming back here from a week ago and looking at the diagram i drew, i can imagine the water just slowly streaming out of the small tap not even close to what i imagined. i dont know what i was thinking. thanks for all your answers from that time, its really appreciated. – person the human Jul 27 '20 at 17:48

## 1 Answer

As a general rule, if you think you've found a perpetual motion machine, you haven't.

People have spent hundreds of years coming up with clever ways to create perpetual motion. All of them have failed. And this is in-line with the predictions of modern physics which say it should be impossible.

In the best case theoretical setting, you should be able to get a water jet that gets precisely to the altitude of the top of the water. You should never be able to get over. Of course, this also involves converting all of the pressure of the weight of the water into velocity. That involves a nozzle that is at least as high as the top of the water, and is typically known as a "tube."

In practice, you will have some drag on the water, mostly in the small tap (but a little bit in the larger body itself). This drag will turn some of the energy into heat, and the result is that the water jet will never quite get to the altitude of the top of the water. It will always come up shy. There are things you can do to minimize how much it comes up shy, but there is no way in physics to get all the way to the top, much less above.

• Cort, did you know a guy named Richard Fesler at your place of work? he's an old friend of mine from UCDavis. – niels nielsen Jun 23 '20 at 5:03