The Impossibility of Perpetual Motion Machines

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Bad ideas come and go in physics. But there’s one bit of nonsense that is perhaps more persistent than all others: the perpetual motion machine. No working perpetual motion machine has ever been experiment verified. All break the laws of thermodynamics. In fact, we classify based on WHICH law of thermodynamics they break. We have perpetual motion machines of the first kind - they violate energy conservation - they pump more energy out than they need to keep running. This includes most of the historical devices. Then there are machines of the second kind - they’re a bit more subtle in their wrongness because break the second law of thermodynamics - extracting energy by reversing entropy. Many modern “free-energy” devices fall into this category. Now the best modern designs are by you - answers to our recent challenge question, which we’ll get to at the end. But first let’s take a look at examples of what other people came up with - this’ll be a fun little journey through some pretty terrible science.

Connor Grey
Creepy Magician
Alex Taylor
Adrien Romeo
Epsilon Centauri
Enoae Andrei

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Sound Waves from the Beginning of Time

Hosted by Matt O'Dowd
Written by Matt O'Dowd
Graphics by Kurt Ross
Directing by Andrew Kornhaber

Designing a perpetual motion machine has a very long history and became quite the craze from the middle ages through the renaissance. The first well-documented design for a perpetual motion machine was from the 12th century. Bhāskara's wheel, named after the Indian mathematician, was embedded with tubes of mercury that would flow from back and forth as the wheel turned. Other types of over-balance wheels followed through to the Renaissance and worked on the same principle. There were also designs that employed the magical-seeming lodestones – magnets. For example, this ramp in which a ball is pulled to the top by a magnet before falling through a hole and rolling to the bottom again. Then there are the self-pumping waterwheels or self-blowing windmills.

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سلطان الخليفي

[-james-]

“Actually, quantum mechanics forbids this” he’s becoming self aware

[johncochran]

The three laws....
1. You can't win.
2. You can't even break even .... Unless it's an extremely cold day.
3. It can't get that cold.

[francescoghizzo]

"Lisa, in this house, we obey the laws of thermodynamics!" (my favourite quote from the Simpsons)

[thefekete]

The hardest part about designing a perpetual motion machine is figuring out how to hide the battery ~ electro boom

[jaysonfred]

You want infinite energy? Just place down a redstone block smh.

[ikemanreed]

Perpetual motion machines seem to be perpetual in the sense that people keep trying to make them

[mikemondano]

The Laws of Thermodynamics:
1.) You can't win or lose. You can only break even.
2.) You can't break even except at Absolute Zero.
3.) You can't get to Absolute Zero.

[quimicoz]

The way I see it, we should build a Perpetual motion machine of the 5th kind.
If it succeds, we have a perpetually working machine.
If it fails, we discovered the 5th law of thermodynamics.
It is a win-win enterprise.

[garryblofeld]

I was going to buy a perpetual motion machine last week, but it only had a six month warranty.

[SprDrumio]

There is one thing that is perpetual tho: people trying to create a perpetual motion machine lol

[Mryoyo]

1. Get a cat, hold upside down.
2. Attached piece of toast to cat's back, butter side out.
3. Drop cat-toast.
4. Cat will always land on its feet, toast will always land butter side up, cat-toast never touches ground spinning endlessly.
5. Attach generator.
6. Enjoy infinite energy.

[robertpearson]

The quest for a perpetual motion machine is itself a perpetual motion machine.

[holo_nside]

Fell asleep to this. Phone fell off my bed and I woke up to "actually, quantum mechanics forbids this"

[oslier]

In this house we obey the law of THERMODYNAMICS

[CeriusDeluge]

I have been working on a perpetual motion machine for years now. I know it's impossible but for some reason I can't seem to stop.

[xINVISIGOTHx]

my dad used to try to make these. He usually used magnets facing in opposite directions so they push apart

[Matyniov]

noone:
universe: "Actually, quantum mechanics forbid this"

[chris]

"I keep designing perpetual motion machines. Ironically, I can't seem to stop."


I forget where the quote comes from though, sorry.

[ronfarrar]

The fun part that gets looked over is efficiency.. the energy gradient of the modern car compared to the first internal combustion engine is so vastly different is like watching gravity driven power compared to the space shuttle. I'm amazed at how they do not fire up imaginations with the challenge to build things that take much less to perform better

[BryanRice]

Just to clarify, ElectroBoom was debunking all the "perpetual motion machines" and other misinformation videos.