Perpetual Motion

This post is part of a series, Nonsense and the Second Law of Thermodynamics. The previous post is entitled The Definition of Entropy.

It is a consequence of conservation of energy and the second law of thermodynamics that it is impossible to build a perpetual motion machine. There are many types of proposed perpetual motion machines.

There is a post that goes into a lot of detail of the various sorts of perpetual motion machines by Kevin T. Kilty, entitled Perpetual Motion.   Rather than go into arcane detail about different types of perpetual motion machines, I think it suffices to refer the interested reader to Kilty's post.

No machine can generate more more energy than put in (first law of thermodyanics, conservation of energy, Noether's theorem).  The first law of thermodynamics states that work can be converted into heat, and heat can be converted into work, but that the sum, the so-called internal energy (E or U) is a conserved quantity.

Nonsense and the Second Law of Thermodynamics

Introduction

The Second Law of Thermodynamics is, perhaps, the most abused physical law of all time. It may be rivaled for that distinction by the Uncertainty Principle, Relativity, and Hawking Radiation, but I think the Second Law probably wins the contest.

There is a plethora of nonsense disseminated on the web and elsewhere that misrepresents what the law actually says. This series is an attempt to curb some of that nonsense.  Along the way, I hope to make some sense of what the second law of thermodynamics actually does say, as well as addressing some of the nonsense that people believe about it.

A Sucker Is Born Every Day!

Snake-oil salesmen are alive and well.  People will buy nonsense if it is marketed correctly.  I enjoyed the review of the wine clip on the Dan's Data Website.  This device supposedly makes wine better by pouring the liquid through a magnetic field.  The review does a good job of explaining the nonsense.

Source

•  Dan's Data:  Dan's Data: Review of the wine clip

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