Perpetual motion describes "Motion that continues indefinitely without any external source of energy; impossible in practice because of friction." It can also be described as "the motion of a hypothetical machine which, once activated, would run forever unless subject to an external force or to ...

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What is the fallacy in this infinite motion machine?

I realize this isn't possible, but I can't see why not, especially if you change the model a little bit so that the balls simply travel through a tube of water on the way up, rather than exactly ...
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4answers
885 views

Why does this perpetuum mobile not work?(Gases and Densities) [duplicate]

I recently came up with the following concept. It is very simple, and may have been thought of before. A picture says more than a thousand words, so here is it explained in a picture: Note that ...
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Can someone explain the science behind MIT's 230% efficient LEDs?

I was reading Gizmodo the other day and I didn't quite understand the Physics behind this. Could anybody shed some light on how this effect actually works?
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Can magnets rotate infinitely?

There are many videos on youtube in which people arranged magnets in circle and rotated one placing in middle of that circle on a shaft, and the magnet (magnet motor) starts madly and continues its ...
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What prevents this magnetic perpetuum mobile from working?

As a child, I imagined this device, which may seem to rotate indefinitely. I have two questions. Is this perpetual motion machine already known? If it is, could you please give some references? What ...
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Why does the “Troll-Mobile” not work?

See image: If I'm not totally dumb the car would move when the right magnet would not be attached to the car, at same distance of the booth magnets. So why would it not move?
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Perpetual motion machine of the second kind possible in nano technology?

First of all sorry for my English - it is not my native language. During my engineering studies at the university the thermodynamics professor told us that the "second law of thermodynamics is not ...
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2answers
452 views

Accidental benefits of seeking perpetual motion? (Science history)

Newton spent much of his life in the fruitless pursuit of alchemy, but along the way discovered and worked-out much else that was real, practical science. And I was thinking about why it is that we ...
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640 views

Why can't a superconductor make a DC motor self sustaining?

Superconducting wire can host a low current magnetic field. I do not know if it supports a corresponding electrical field. Can a superconducting wire that sustains a current accelerate a DC motor? ...
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226 views

Thought Experiments on black holes, (im)possible perpetual motion and minimum mass for photographic plates

Consider a black hole in vacuum at Temperature T. The setup that I am interested is a one that collects thermal photons from a black hole by enclosing in a spherical photographic plate and then ...
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698 views

Quantum perpetual motion

Perpetual motion describes hypothetical machines that operate or produce useful work indefinitely and, more generally, hypothetical machines that produce more work or energy than they consume, ...
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516 views

Vacuum energy and perpetual motion

The part of the Einstein equations of general relativity referred to vacuum energy, introduce a repulsive term in gravity. This means that as the space become bigger and bigger, vacuum part become ...
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364 views

Energy Conservation Law validity

I will probably be laughed out of town for saying this, but why can't the Energy Conservation Law be broken? Everybody thought electricity to motion was impossible until Faraday made his motor, ...
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1answer
396 views

How to understand Feynman's reasoning about perpetual motion?

I'm studying Feynman's Lectures on Physics, and I'm not really understanding his reasoning here: Consider weight-lifting machines $\overline{}$ machines which have the property that they lift one ...
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6answers
215 views

Extracting heat energy without a heat engine

Is it possible to extract the molecular kinetic energy from a system directly (without the use of a heat engine / temperature gradient) and convert that to another form of energy, such as electricity, ...
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3answers
1k views

Does Nantenna (nano antenna) violates 2nd Law of Thermodynamics?

Does Nantenna (nano antenna) violates 2nd Law of Thermodynamics ? Nantennas absorb infrared heat and convert it in direct current. Quote from Wikipedia: He did not discuss whether or not this ...
3
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1answer
118 views

Perpetual motion in spaces of different gravity?

Imagine two locations with different amounts of gravity. I carry up a weight in low gravity, move it on this height over to the other place, and let it fall down there with higher gravity. Wouldn't ...
3
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1answer
490 views

Are perpetual magnetic motors a scam? [duplicate]

I read articles and watched videos and more videos where people say they've built perpetual magnetic motors. I do not see any proof that this can work and also I do not see proof that it is wrong. ...
2
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1answer
153 views

greenhouse trap and perpetual motion

Greenhouse gases keep the planets warmer than they normally would. But, as with electrons trapping photons, I feel that thermodynamics is violated here. Is the violation allowed if energy is trapped ...
2
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1answer
3k views

“Troll physics”: Buoyancy for infinite power [duplicate]

Possible Duplicate: What is the fallacy in this infinite motion machine? Most of the "troll physics" images I can figure out, but this one has me stumped. What is broken about the following ...
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2answers
2k views

Why can't electromagnetic radiation from magnets be used for apparent perpetual motion?

If electromagnetic radiation represents a transfer of energy, then does a permanent magnet represent unlimited energy, and if so, why can't magnets be used for perpetual motion? Even if permanent ...
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1answer
171 views

Does perpetual motion machine really exist?

I recently saw a video on Youtube about a perpetual motion machine. Here is the link: http://www.youtube.com/watch?v=OS1KXMsE2qk It's on Robert Boyle's flask. Where does the energy come from?
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1answer
555 views

Why this perpetuum mobile can't be possible? [duplicate]

I know that this won't work but I'm asking Why? Becuase as far as the vehicle POV - there is a force which drags him to the right. Isnt $F=ma$ applies here? What is that im missing?
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1answer
63 views

The Spinning Log “Perpetual Motion” problem, and my attempt at a solution

So I was introduced to this "perpetual motion" riddle a few weeks ago. The problem goes like this: we all know perpetual motion machines are not possible, but this riddle seems like it should work as ...
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208 views

Asynchronous generator run in vacuum chamber

what will be happen if we put asynchronous generator in vacuum chamber & run it above its synchronous speed. After reaching its over synchronous speed we will cut off electrical supply. Can it run ...
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5answers
426 views

Why isn't perpetual motion possible, even though we are so technologically advanced?

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 ...
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150 views

Matter - Antimatter Reactory Practicality

With current technology, would the energy released by a matter-antimatter annihilation be more than the energy needed to created the antimatter in the first place? Would it be worth it? Just curious, ...
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369 views

Can anyone analyze this perpetual machine that a Norwegian built?

Take a look at this video: http://www.youtube.com/watch?v=tlx2PgESXhs It shows a machine that a Norwegian artist built. It seemingly keeps going forever. They filmed it over 3 days and it kept going ...
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Are orbiting planets an example of perpetual motion?

I understand that perpetual motion is impossible, but I became confused when a friend of mine told me that the orbits of the planets is an example of perpetual motion. Will earth's orbit ever end, and ...
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1answer
53 views

Please explain the flaw in this picture [duplicate]

So I saw this picture on my google+ feed and I immediately know why it wont work. But I'm having trouble explaining to myself and others exactly why. Without using anything overly complex, can anyone ...
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1answer
1k views

Are the perpetual machines in this video really perpetual?

This video lists a number of perpetual motion machines that have been proposed throughout history: Robert Boyle's Self-Flowing Flask A "perpetual train" using rolling cones F. G. Woodward's hoop ...
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3answers
112 views

A potential perpetual motion machine?

If I were to freeze a superconductor, the ones made up of yttrium barium copper oxide, with liquid nitrogen and placed it on one of those strong neodymium magnets, it should float right? Now what ...
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0answers
40 views

Thought experiment regarding perpetual motion machines and paradoxes [closed]

A paradox (Ex.: if someone goes back in time to kill their own grandfather, then they won't exist, but then they wouldn't be able to go in time to kill their grandfather, but then they WOULD exist, ...
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1answer
269 views

Is magnetic wheel possible?

I once tried to make a magnetic wheel using different shaped magnets and placing them in different orientations and of different shapes.But it did rotate making a small angle ie it didnt rotate even a ...
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596 views

Magnetic field of solenoid in cone shape

I have done some drawings of the magnetic fields of cone shaped solenoid electromagnets. I based this on the work of Tesla and some explanations of Bashar, known as the Bashar Cones. I found very ...
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“This is not a perpetual motion machine, because reservoir temperatures are changing.” Is it a valid argument?

I've already faced this situation several times: given a statement (in area of thermodynamics) I used it to provide an example of some perpetual motion machine (of first or second kind). Therefore, I ...
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4answers
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Free energy device - QEG. Is this for real?

I'm not a physicist but I ran across reports on the web of a so called over unity or free energy device that has been created that supposedly works. It's called the QEG. Does this seem legit or is it ...
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4answers
396 views

Whats wrong with this perpetual machine?

Consider a cube of mass M resting on a rough surface such that the coefficient of friction between the cube and the surface is K. So in order to just slide the cube I need to apply a minimum force of ...
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2answers
74 views

Why isn't a pendulum clock considered a perpetual machine?

Why do people say that a perpetual machine is one that runs for eternity? Wouldn't a machine that runs taking no energy from outside but sometimes needs to be restarted, such as pendulum clock, be ...
0
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2answers
863 views

How does the Milkovic Two-Stage Mechanical Oscillator Pendulum-Lever System work?

See http://peswiki.com/index.php/Directory:Milkovic_Two-Stage_Mechanical_Oscillator The Two-Stage Mechanical Oscillator Pendulum-Lever System is very simple, yet very puzzling because it appears ...
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1answer
101 views

Superfluid Fountain

I was wondering how a super fluid fountain can flow indefinitely without violating energy conservation.
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1answer
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Would a generator in vacuum/space provide electricity endlessly?

At it's simplest, electricity generation is achieved by induced voltage due to a changing magnetic field. In a vacuum in the absence of friction, would the initial spin imparted to the rotor of a ...
0
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3answers
117 views

Magnet motor free energy generator [duplicate]

Is it possible to run a fan without electricity? like the one show on this website? http://free-energi.com/index.php?a=2
0
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1answer
52 views

Magnetic Attraction in Space [closed]

If I were to attach a 1 inch diameter magnet to lets say a half pipe, that it fits perfectly in, and attach a 1 in diameter piece of iron close enough for the magnet to assert its attractive pull, ...
0
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1answer
247 views

Pendulum water pump - apparent free energy

I've seen plans for a pendulum oscillator water pump that is claimed to pump a large volume of water (100 gallons) from a well of 100 feet deep. The pendulum consists of a 100 pound weight raised 6 ...
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1answer
214 views

Repulsive Magnetic Hammering Experiment

I have been thinking about something thing... I want to attach four or any number of magnets with arms to an axle.. Blue dots be magnets. Its is not a wheel configuration, all arms can move ...
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Curious about this perpetuum concept

I know it's not possible to build a perpetual motion machine, but I still got this concept running in my mind. If you take a (longer)copper coil, and insert an axis through it(right-angled) with a ...
0
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2answers
76 views

What physical conditions would allow for this kind of perpetual seesaw

I'm working with a simulator(Box2D) and need to create these conditions. I have a perpetual seesaw with two objects on either side. I'd like for the following conditions to be met. The first ...
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0answers
46 views

How to interpret Lenz's law in STR?

By the Lenz's law, when a charged particle goes through a coil it generates a magnetic field. This field generates a current in the coil, slowing down the particle. But by Special Relativity (STR), ...
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How long will a permanent magnet retain its properties when used in a votrexing magnetic field?

How long will a permanent magnet remain effective when used within a vortexing magnetic field? I am refering to both the magnets making the field, and the magnet in the center that spins within the ...