If this is released from rest, which way would it tip? According to the See-Saw Balance machine, it would tip to the left since the ball is pushing on the support and the support pushes on the left side. Nice idea, but wrong. Let me draw that same support with the forces acting on it. If you held the board steady, that support would be at rest and not rotating, so the net force and the net torque on the board must be zero. This probably is the diagram a perpetual motion person would draw: a b Amber M. Aiken, Ph.D. "Zero-Point Energy: Can We Get Something From Nothing?" (PDF). U.S. Army National Ground Intelligence Center. Forays into "free energy" inventions and perpetual-motion machines using ZPE are considered by the broader scientific community to be pseudoscience. There are many designs on the internet that claim to be working designs for perpetual motion machines. If you look at those designs, it's not too farfetched to think that some of those machines could (if engineered correctly) move without stopping. And if we could do this, the implications would be staggering. We would essentially have an eternal source of energy. More than that, it would be free energy. There is a scientific consensus that perpetual motion in an isolated system violates either the first law of thermodynamics, the second law of thermodynamics, or both. The first law of thermodynamics is a version of the law of conservation of energy. The second law can be phrased in several different ways, the most intuitive of which is that heat flows spontaneously from hotter to colder places; relevant here is that the law observes that in every macroscopic process, there is friction or something close to it; another statement is that no heat engine (an engine which produces work while moving heat from a high temperature to a low temperature) can be more efficient than a Carnot heat engine operating between the same two temperatures.

Weisberg, J. M.; Nice, D. J.; Taylor, J. H. (2010). "Timing Measurements of the Relativistic Binary Pulsar PSR B1913+16". Astrophysical Journal. 722 (2): 1030–1034. arXiv: 1011.0718. Bibcode: 2010ApJ...722.1030W. doi: 10.1088/0004-637X/722/2/1030. S2CID 118573183. Impossibility [ edit ] October 1920 issue of Popular Science magazine, on perpetual motion. Although scientists have established them to be impossible under the laws of physics, perpetual motion continues to capture the imagination of inventors. [note 2] Unfortunately, thanks to the fundamental physics of our universe, perpetual motion machines are impossible. Even machines that extract energy from long-lived sources - such as ocean currents - will run down when their energy sources inevitably do. They are not perpetual motion machines because they are consuming energy from an external source and are not isolated systems. Goldstein, Herbert; Poole, Charles; Safko, John (2002). Classical Mechanics (3rded.). San Francisco: Addison Wesley. pp. 589–598. ISBN 978-0-201-65702-9.

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Perpetual motion, on season 8 , episode 2". Scientific American Frontiers. Chedd-Angier Production Company. 1997–1998. PBS. Archived from the original on 2006-01-01. Matt Visser (3 October 1996). "What is the 'zero-point energy' (or 'vacuum energy') in quantum physics? Is it really possible that we could harness this energy?". Phlogistin / Scientific American. Archived from the original on July 14, 2008 . Retrieved 31 May 2013. Alt URL Epistemic impossibility" describes things which absolutely cannot occur within our current formulation of the physical laws. This interpretation of the word "impossible" is what is intended in discussions of the impossibility of perpetual motion in a closed system. [22] For the sake of argument, let's just say that somehow, we are able to build a perpetual motion machine. Will we be able to get energy from it? Yes, but only up to the energy that is used as an input to start the movement. A perpetual motion machine in real life will just be an energy storage. We must remember that the energy cannot be created; it always has to come from something.

Processes or articles alleged to operate in a manner which is clearly contrary to well-established physical laws, such as perpetual motion machines, are regarded as not having industrial application. [32]A capillary action-based water pump functions using small ambient temperature gradients and vapour pressure differences. With the "Capillary Bowl", it was thought that the capillary action would keep the water flowing in the tube, but since the cohesion force that draws the liquid up the tube in the first place holds the droplet from releasing into the bowl, the flow is not perpetual. Ok, I guess this is the time to fess up. It doesn't work as smoothly as shown in the video. Although I think it works pretty well, it took a few takes with the camera to get clean shots. Roy, Bimalendu Narayan (2002). Fundamentals of Classical and Statistical Thermodynamics. John Wiley & Sons. p.58. Bibcode: 2002fcst.book.....N. ISBN 978-0470843130.

quote originally from Leonardo's notebooks, South Kensington Museum MS ii p. 92 McCurdy, Edward (1906). Leonardo da Vinci's note-books. US: Charles Scribner's Sons. p.64. The Work-Energy Principle is wrong. OK, this isn't very likely. We have used this principle for a long time and it always works. It would be crazy to have a stupid wood-and-ball toy prove that energy isn't conserved.Examples of decisions by the UK Patent Office to refuse patent applications for perpetual motion machines include: [33] The perpetual myth of free energy". BBC News. 9 July 2007 . Retrieved 16 August 2010. In short, law states that energy cannot be created or destroyed. Denying its validity would undermine not just little bits of science - the whole edifice would be no more. All of the technology on which we built the modern world would lie in ruins. Buoyancy is another frequently misunderstood phenomenon. Some proposed perpetual-motion machines miss the fact that to push a volume of air down in a fluid takes the same work as to raise a corresponding volume of fluid up against gravity. These types of machines may involve two chambers with pistons, and a mechanism to squeeze the air out of the top chamber into the bottom one, which then becomes buoyant and floats to the top. The squeezing mechanism in these designs would not be able to do enough work to move the air down, or would leave no excess work available to be extracted.

Perpetual motion is the motion of bodies that continues forever in an unperturbed system. A perpetual motion machine is a hypothetical machine that can do work infinitely without an external energy source. This kind of machine is impossible, as it would violate either the first or second law of thermodynamics, or both. [2] [3] [4] [5] These laws of thermodynamics apply regardless of the size of the system. For example, the motions and rotations of celestial bodies such as planets may appear perpetual, but are actually subject to many processes that slowly dissipate their kinetic energy, such as solar wind, interstellar medium resistance, gravitational radiation and thermal radiation, so they will not keep moving forever. [6] [7] Powell, Devin (2013). "Can matter cycle through shapes eternally?". Nature. doi: 10.1038/nature.2013.13657. ISSN 1476-4687. S2CID 181223762. Archived from the original on 2017-02-03.Parts, Form, and Content of Application - 608.03 Models, Exhibits, Specimens". Manual of Patent Examining Procedure (8ed.). August 2001. In some cases a thought (or gedanken) experiment appears to suggest that perpetual motion may be possible through accepted and understood physical processes. However, in all cases, a flaw has been found when all of the relevant physics is considered. Examples include: Statements 2 and 3 apply to heat engines. Other types of engines that convert e.g. mechanical into electromagnetic energy, cannot operate with 100% efficiency, because it is impossible to design any system that is free of energy dissipation.