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Why perpetual motion wouldn't be possible if we are so technological advanced?

It is just a thing that I was wondering for too long. I mean, we are able to create so powerful permanent magnets, like neodymium magnets which can store an massive quantity of energy for a long period of time, but we are not able to use that energy at all. Why?

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From the article: "...perpetual motion in an isolated system would violate the first and/or second law of thermodynamics." do you understand these laws? I ask so the answer can be targeted to the right level. The reasons we don't have perpetual motion machines aren't technological limitations, they're based on our understanding of the fundamental nature of energy and information, and how they move around. –  Robert Mastragostino Mar 23 '13 at 23:42
    
@RobertMastragostino But wouldn't you say that the fundamental nature of energy limits technology? One perpetual motion machine (don't quite remember the "type") has no friction but we know that friction exists. Wouldn't a perpetual motion need to be free of the effects of entropy to be in "perpetual motion"? This is an interesting discussion for a sophomore level class that I teach! :) –  drN Mar 24 '13 at 0:25
    
@drN I would absolutely say that physics limits technology, but I only meant to imply that our current technological prowess (or lack thereof) isn't the limiting factor in this case. –  Robert Mastragostino Mar 24 '13 at 2:21
    
@drN perpetual motion machines are the dream of getting energy out of nothing, not whether something can be in perpetual motion. In that sense the electrons bound to the nuclei are in perpetual motion. –  anna v Mar 24 '13 at 6:19
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Yes, we can make permanent magnets using energy which is stored in the magnetic field of the permanent magnet. Any device thought up that would draw energy utilizing the magnetic field would slowly demagnetize the magnet. Energy is conserved and this is an experimental fact. –  anna v Mar 24 '13 at 6:20
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2 Answers

"Nature, to be commanded, must be obeyed".

If perpetual motion is impossible in principle, no technology, no matter how advanced, will make it possible.

By the way, perpetual is longer than any long period of time.

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We can create lots of things that can store energy for long periods of time - magnets, capacitators, batteries...but we must do work to put that energy in before taking it out. It's like a bank account that couldn't be overdrawn. Perpetual motion would be like a bank account that magically had money appearing in it every day without anyone depositing money into it.

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