I was surprised to see an effect that's actually real, and not a hidden motor or something like that. I believe this experiment can feasibly be repeated. The principles behind it make sense.
The driving force comes from the density difference in the cup versus in the pipes. The cup has very few bubbles in it compared to the pipe. Why? Because:
- The bubbles in the cup have an exit strategy - floating to the top. Not so in the pipe.
- The pipe has greater wall area to volume ratio. So it likely has more nucleation sites for the bubbles.
If I were recreating this, I would design the pipe to turn horizontal/vertical as close as possible to the bottom of the cup, in order to help maximize the driving pressure. Also, make sure to use the soda/beer right after opening it.
This experiment shows (not perpetual motion) that carbonation contains stored energy in some sense. More specifically, the process of a carbonated drink decaying into un-carbonated liquid and CO2 gas liberates extra energy. A small fraction of that energy is harvested here to drive the flow.
Very good science project.
In order to demonstrate that it is not perpetual motion, either allow it to run to its full conclusion, or try it again with soda that has sat out for a day. The data should support the hypothesis that the driving force to power the flow comes from stored energy in the carbonation.
Is the reason we don't have any perpetual motion machines because of
the first law of thermodynamics?
That's one of the reasons, and it applies to a perpetual motion machine of the first kind, a machine that can produce work without any energy input in violation of the first law (conservation of energy).
There is also a perpetual motion machine of the second type, which is a machine that can operate in a cycle exchanging heat with only one temperature reservoir completely converting 100% of the heat into work. This machine violates the second law of thermodynamics.
Would it be possible to create one if (for example) there was a wheel,
and it had a push– if it was frictionless, and in a vacuum, would it
spin forever?
What you are describing is sometimes call a perpetual motion machine of the third kind. It is based on the idea that motion, once started, can continue forever. This requires the complete elimination of any and all forms of friction, which is not possible, even when operating in a vacuum (which in practice is never perfect). Even space is not completely free of particles.
Also, would gravity matter if friction wasn't in the equation?
Not quite sure what you mean by "would gravity matter". As the range of gravity is essentially infinite, it is impossible to completely isolate the machine from gravity and gravitational forces (Newtonian gravity).
Hope this helps.
Best Answer
Wikipedia describes Perpetual motion as motion that continues indefinitely without any external source of energy. This is impossible in practice because of friction and other sources of energy loss.
Of course, this is practically impossible since you can never fully eliminate the frictional forces. Although we say it’s impossible, people still like to come up with ideas. Perpetual motion machines are sort of like playing the lottery. People think they have a much higher chance of winning than their actual chance of winning.
Perpetual motion describes motion that continues indefinitely without any external source of energy is impossible in practice because of friction and other sources of energy loss. It violates the first or second law of thermodynamics.
See this detailed explanation at wired.com with a kind of experimentation.