Stack Exchange Network

Stack Exchange network consists of 175 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.

Visit Stack Exchange

Questions tagged [perpetual-motion]

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 wear". There is a scientific consensus that perpetual motion in an isolated system would violate the first and/or the second law of thermodynamics.

0
votes
1answer
45 views

Infinite Electricity from Photon Inside Closed Box with Magnet Attached in a Coil? (Thought-experiment)

Let's say I have a very large box with a magnet attached to the outside. Inside the box there is a perfect mirror on each side. I open my box and quickly shoot in one photon before shutting it. After ...
1
vote
1answer
48 views

Perpetual magnetic attraction

There are two magnets, M1 and M2. Let's say that there is an attractive force existing between M1 and M2. M1 is attached to a surface, while M2 is free to move. Now slow this motion down, and M1 is in ...
-4
votes
1answer
50 views

Perpetual Motion Machine 1: Magnetic Superconductor Loop Generating Energy with Piezoelectrics [closed]

I know there are a lot of perpetual motion machine designs out there, but I haven't found one that looks like this one. I will use this diagram. Assume the entire ring is made of a superconducting "...
-2
votes
1answer
57 views

Energy balance of this machine is positive. What is wrong? [duplicate]

Machine on this picture is inspired by video: https://www.youtube.com/watch?v=rxFXsoqbfrk There must be error in the computation of energy balance or there is another negative energy. Can you help ...
-1
votes
1answer
66 views

can we use the power of ice to float to make free electricity?

ice and water have a volume to weight ratio of 12/11 so 11 tons of ice will support 1 ton of weight 1 ton of ice takes 1000 watts or 12000 b.t.u. of energy to be produced question is , at what ...
12
votes
3answers
9k views

Why can't we make a perpetual motion machine by using a magnet to pull up a piece of metal, then letting it fall back down? [duplicate]

Obviously, a perpetuum mobile isn't possible by any law in physics, because energy can't be "created" or "destroyed", only transformed. This said, I've had an idea for a perpetuum mobile and can't ...
14
votes
16answers
9k views

Can we use the stored gravitational potential energy of a building to produce power? [closed]

There are skyscrapers sitting and pushing on the ground with tremendous weight. Is it possible to convert this weight/force to harness energy to power the building? Maybe build the building on top ...
0
votes
5answers
139 views

Harnessing molecule vibration energy

Disclaimer: I am learning physics for fun, please dont kill me but explain where I am wrong. As I understand all molecules have a lowest energy state in which they posses some amount of momentum even ...
0
votes
0answers
44 views

Is there an upper limit on entropy density?

I would like to sell you a perpetual motion machine that works by making the insides of a box continually more messy. The engine comes packaged with a physicist who will continually discover new ...
0
votes
0answers
36 views

Perpetual Motion and Thermodynamics [duplicate]

How does the second law of thermodynamics disprove all perpetual motion machines?
2
votes
1answer
65 views

Doesn't expansion of space not allow a perputual motion?

Well consider the following thought experiment: We have a tool to extract/transform "nearly all" potential gravitational energy into other forms of energy. We can theoretically make such an object (...
1
vote
2answers
126 views

Perpetual motion using mass defect

First off, I know this wouldn't work due to it breaking thermodynamics and that there would also be heaps of energy dissipated to the surroundings, and fusion doesn't work yet, but I'm more interested ...
1
vote
2answers
44 views

Is mass-energy conversion contradicting energy conservation? [duplicate]

If mass can be transformed into energy, and energy transformed back into mass, isn't this at odds with the law of conservation of energy? Because this would mean, that in theory, it would be possible ...
1
vote
2answers
85 views

Derivation of 2nd law of Thermodynamics from ergodicity assumption

In Wikipedia it is claimed that: Assumption of the ergodic hypothesis allows proof that certain types of perpetual motion machines of the second kind are impossible. Since perpetual motion ...
2
votes
1answer
133 views

Is it possible to create a limitless power by firing rocks from the moon to Earth? [closed]

Here is my idea for a limitless* power. A gun on the moon fires moon rocks towards the Earth. The moon rocks fall in Earths gravity picking up speed and smash into Earth's atmosphere generating huge ...
0
votes
3answers
196 views

Does a heat engine inside of a refrigerator increase efficiency?

Consider a normal refrigeration cycle, except a heat engine runs off of the temperature difference between the evaporator and the condenser, as shown below. This heat engine powers the compressor, so ...
0
votes
1answer
72 views

Is self-perpetual system possible?

As I was reading a intermediate part-2 book I come to know that self-perpetual system is not possible. So i wanted to know if it is possible or it's completely impossible.
-2
votes
1answer
71 views

auto-refilled nuclear fusion generator [closed]

I read in a science article that in a nuclear fusion reactor, the energy we bring to the reaction is multiplied by a coefficient q. This coefficient needs to be at a certain level (around 7 if my ...
-3
votes
2answers
119 views

If there were no inertia would perpetual motion be possible? [closed]

Is it not inertia that makes a flywheel resist being put into motion? And if that is true, is inertia a consequence of being unable to create energy, i.e., why perpetual motion machines do not in fact ...
0
votes
1answer
45 views

Is it possible to generate conditions such that the temperature difference created by current is high enough to sustain it?

We know that current can generate temperature difference and vice-versa. But is it possible to generate such conditions that the temperature difference created by current is high enough to sustain it?...
-1
votes
1answer
1k views

Can Bhaskara's Wheel increase the efficiency of wind mills?

Bhaskara's wheel is an ancient attempt at perpetual motion. The idea is that gravity will pull the water toward the center for the bottles at the top and toward the ends for the bottles falling to ...
0
votes
1answer
249 views

Magnetic Turning Wheel [duplicate]

So a few years ago I came up with the idea of a magneticly powered wheel that could be attached to a generator and power it, it would not be infinite as over time magnets lose their power yet I think ...
4
votes
4answers
204 views

Feynman and Perpetual Electron

In the paragraph 1–2 "Matter is made of atoms" of the first Volume of his lectures, the great Feynman says that electrons are in a perpetual motion. Now, i'm new to physics and i don't know quantum ...
-5
votes
2answers
164 views

Is this a new form of renewable energy? (sand) [closed]

Can we make a machine that takes a mass of sand from the top of a sand dune keeps it in a box. Then moves it horizontally until it is hovering above the lowest point near the slipface of the dune. ...
3
votes
0answers
312 views

Can water drip from a capillary tube top? Perpetual motion?

In a normal capillary tube (ex: tube A), where the water doesn't travel as high as the tube's height, h, the meniscus formed is "normal" (concave, as seen in tube A). From previous posts, I ...
1
vote
1answer
247 views

Capillary Perpetual Motion

Can anyone figure out what is wrong with this perpetual motion machine? What part of it violates physics? I found it on a website a while ago, and I couldn't figure out what was wrong with it. Thanks, ...
0
votes
0answers
42 views

Are attempts to extract useful work from spontaneous decreases in entropy an example of Maxwell's demon?

Something I see often in forums discussing future energy sources is perpetual motion of the second kind. Rather than outright denial of the second law, however, they say the fluctuation theorem shows ...
-3
votes
1answer
52 views

Can total internal reflection be used to create a source of light which will never be used up?

I am a science student and was thinking of something great for a science model , Thought of this, please tell me will this work and also suggest some other ideas that can be used to make good working ...
0
votes
0answers
159 views

How to debunk this perpetual motion machine? [duplicate]

I know it's impossible. I normally find the flaw behind the principle, but this one is hard to crack. The two wheels are geared together, so that no magnet on one wheel "backlashes" the wheel in a way ...
-3
votes
1answer
77 views

Can it be possible “Perpetual Atmospheric Engine”? [closed]

Source: Perpetual Atmospheric Engine-https://www.youtube.com/watch?v=Q3t-NkfpFOc My motivation to believe this idea comes from "Pythagoras Cup (Greedy Cup)", like in this cup, there is no balanced ...
-3
votes
1answer
71 views

Can my theory work for letting the swinging work?

This is my theory, will it stop after few hours? why would it stop? i have on top S to S to repel then i have N S to attract, to produce random force for the swing. Then i have large N N repel to push ...
2
votes
2answers
282 views

How much current is induced by a free falling magnet?

Assume we have a set of $N$ coils stacked vertically on the surface of the Earth, up to a height of $h$, and that we drop a magnet from the top of the coils, which then falls due to gravity through ...
0
votes
0answers
138 views

why this perpetual motion engine does not work and does not break the law of energy conservation?

I came-up with this idea when i was 10 years old , I am not claiming that it is working , I just want to know why it doesnt if it doesnt ? This engine is supposed to produce infinate energy from ...
-4
votes
2answers
314 views

Is there any proof that a perpetual motion machine of the second kind is not possible?

According to The statistical nature of the 2nd Law of Thermodynamics, the second law of thermodynamics probably hasn't been proven to be absolute. That doesn't necessarily mean it hasn't been proven ...
0
votes
0answers
62 views

Can torsional force be used to harvest gravity?

I am curious if an idea I have will work or if it is the result of a lack of understanding of the physics involved. I am expecting to be disproved. Please excuse any lack of understanding on my part ...
2
votes
2answers
104 views

A conceptual propulsion device based on instantaneous energy transfer of relativistic mass

Setup Consider two objects $O_1$ and $O_2$ of mass $m$ each. The objects are connected one to another with a rod of say length $2\cdot l$. At the middle of the rod, $M$, there is a rotational joint ...
0
votes
1answer
70 views

Disprove this violation of conservation of energy setup

Violation of conservation of energy thought experiment: Let us imagine an air compressor is invented with incredible efficiency. This compressor will compress a gas and recover back 99% percent of ...
-3
votes
1answer
147 views

Why is Escher's waterfall considered a perpetual motion machine of the first kind? [closed]

I know that perpetual motion machines can't work because of friction, but intuitively I thought that Escher's waterfall (https://cdn.churchm.ag/wp-content/uploads/2011/04/waterfall-illusion-...
1
vote
0answers
133 views

Demagnetization and the illusion of perpetual-motion machines

Every now and then, a putative inventor showcases his perpetual motion machine which he/she claims is truly perpetual, only to find-out that the invention is a do-nothing machine that relies on a well-...
-1
votes
2answers
126 views

What exactly contradicts the usage of electric generators as perpetuum mobile?

A friend has been talking to me about using various electric generators in order to create a perpetuum mobile that can be used for various especially in cars. Of course I instantly said that it doesn'...
1
vote
0answers
41 views

Are the planets revolving around the sun in perpetual motion? [duplicate]

I was wondering if the planets revolving around the sun are an example of perpetual motion. Will they ever stop the revolution?
-4
votes
2answers
272 views

What is wrong with my perpetual motion machine model? [closed]

I know that perpetual motion machines are not possible and I want to know the reason why will this machine not work. The Car B has a magnetic bulge on top of it and Car B can only move forward. It ...
-2
votes
3answers
231 views

Continuous Ball Fall perpetual motion machine [closed]

Before I get to it. It must be absolutely clear that this ball will, when dropped from a great height, gain a velocity enough to spin this wheel connected a dynamo. And if there was a water ...
3
votes
1answer
239 views

Is this “Permanent magnet gun” real or fake?

There are several videos on youtube describing linear accelerator built solely from permanent magnets, put like this: I find it hard to believe that this can work because if it did, it would be ...
-2
votes
1answer
75 views

Infinite gravity “train” [closed]

I am trying to do some simple physic engine, and when I implemented gravity, I could see this : You can Imagine this as planets and they're attracting each other so in this situation, they can ...
-3
votes
3answers
426 views

Is it possible to use the physics of a pendulum to generate Electricity

Say we have a friction less pendulum and it extends over a 1/2 of a foots length with 3 bobs. These bobs are kept in motion by magnets of the opposite force that have been placed on a metal tray that ...
-3
votes
1answer
60 views

What's wrong with this car model? [duplicate]

Even if every possible attempt to avoid stuff that can be avoided (like it will topple, the connectors will break, it won't overcome the rolling resistance, etc, etc) is made What if one of the ...
0
votes
2answers
113 views

Why can't hydro-static pressure be used in unison with magnetic fields to generate electricity?

Let's say you have a fixed pipe, linked at one end to the surface and the other submerged connected to a detachable chamber as shown below: The pipe is fixed in its position by a barge of some sort ...
0
votes
1answer
71 views

Why can't you generate electricity by transferring objects between fluids of varying densities?

Let's say you have an object travelling between two immiscible liquids like water and oil in an arrangement shown below. (water being blue and oil being yellow) The object is a cubic meter weighing ...
-4
votes
1answer
92 views

Can perpetual machines be made? [duplicate]

Nowadays there is a lot of questions regarding perpetual motion and perpetual machines. So, can we make one? i searched a lot but i am am still not satisfied with the answers and with thermodynamics.