Perpetual energy machine problem


I’m trying to make a perpetual energy machine with dominos. The machine uses gravity as its energy source. The dominos are attached to the base plate with hinges to keep them in place. I want the dominos to return upright somehow, so the toppling can repeat itself. Realistically, it won’t be indefinite, but I’d like to figure out a way to repeat the chain reaction at least once. Any ideas?

Here’s what I’ve got so far:

  1. The force of a falling domino lifts up the domino behind it with leverage. With leverage, I think it’s possible for a domino to lift another domino of the same weight.

The model (made with MSPhysics):
Perpetual Dominos 1.skp (2.4 MB)


I’m afraid this idea has the same problem that every perpetual energy machine has, physics. The laws of thermodynamics say “no free lunch”. In converting potential energy into kinetic energy (domino) falling over is being driven by the stored energy of sitting upright, that energy was stored there when you burned calories in your arm to lift it up against gravity. There is no lossless system, the energy of a falling domino will never quite equal the amount needed to stand one back up, the way a pendulum will never return to quite the same height after each swing. All “work” takes fuel.

You could make it appear that this was happening, by magnets, or compressed air jets, or by tilting the table in a circular motion, but those would all be ways of adding energy back into the system.


All you need to do to make this work is… sorry forgot you wanted me to ignore your threads.

But a curved pin in the floor could be used as an actuator to reset the dominos.


The energy of a falling domino won’t equal the amount needed to stand one back up, but the energy of a falling domino can fall on a lever capable of exerting enough force to lift one back up. The force of the falling domino can be multiplied by leverage.

@Box That’s a good idea. I already considered it, but MSPhysics can’t simulate holes unless they’re split into groups. It’s more work, but I agree it’d be better than my example.

You’re welcome to comment on my threads.


A lever, is a method of mechanical advantage that trades distance for force. It does not add energy, it converts energy. A lever can multiply the input force so that 1 pound input = 10 pounds output, but the input side will need to move 10x distance for 1x distance on the output side. Again, no free lunch, you can convert the way the energy does work, but you can’t get more work out than you put in. The fulcrum, or center of the seesaw is the big equal sign and the energy on both sides is always equal. So no matter how clever is your lever, the energy of one domino falling does not = the energy needed to stand one up.


I’m aware it’s physically impossible to make a perpetual energy machine, but I figured I’d try anyways. :sweat_smile:


The losses in any perpetual motion machine are due to friction. It should be possible to construct one using MSPhysics if you set the friction to zero. After all, it’s only a model :wink:




Gravity can be used as fuel. There are gravity powered flashlights and stuff. Gravity is a constant force, so maybe it’s energy can be constantly harvested.

In 0 gravity, dominos don’t even work because they lose energy every time one moves. There’s no gravity to fuel the movement.

In gravity, dominos will move as long as there are more dominos to topple. Gravity fuels the dominos, potentially perpetually (if you had infinite dominos).

Other forces like wind or water can be harvested with propellers and wheels. I wish gravity could be harvested too. Point is, there is a fuel in my machine. It’s gravity.

People say gravity isn’t energy, but I disagree because it’s a constant movement of attraction. Even though something is still, gravity is still moving it towards the ground relative to were it would go if there weren’t gravity. For example, if an object is outside & there’s a mild 1 mph breeze, then then object will be still. If there was no gravity, then the object would be pushed away by the breeze at 1 mph. I’m saying that gravity is moving the object downwards constantly, even when the object is still it’s moving relative to where it would go without gravity. I think gravity moves things the same way that water moves things. The stream moves things relative to where they’d go if they weren’t in the water and gravity moves things relative to where they’d go if they weren’t in our gravity.

Gravity moves things down perpetually & uninterruptedly, so I think it’d be the perfect fuel for a perpetual energy machine.


OK, good luck on the patent for that. You’ll be rich! Then explain it to a physicist.


That is called a ‘force’, the moving will stop if the upforce is equal.

Gravity doesn’t fuel them, you put energy in them while resurecting them, in real life, it’s called ‘kinetic energy’ in computersimulations, it still costs energy to let the bits do their thing…

This is like forming a circle with some friends, all starting with 10 dollars, and passing one dollar to the person who stands next to ya, you’ll be rich at the end of the day!!

There are two ‘forces’ at work in this universe, one strives at gaining more entropy (disorder or degree of chaos) and the other is the opposite: negentropy or the striving towards unity. The latter costs energy and the other releases it.


Apologies if these ideas are meant to be somewhat tongue in cheek - I can’t quite tell - but I find discussions like this to be completely useless when any of the participants won’t acknowledge that they don’t know basic physics or thermodynamics yet persist in raising ideas that were proved to be impossible nonsense about 100 years ago!


Well this is not how we actually look at gravity. But I’m assuming you are sincere as you keep coming back and asking intersting questions and you seem genuinely curious, so let’s run with the idea.

Gravity as a “fuel”. If we imagine it like that we can see that many of our systems today work on a principle that could be described in this way. Hydroelectric power which keeps the lights on for billions is run by a big lake full of water being pulled downward, and that attraction or “gravity” is being tapped for work. In that sense a lake behind a dam is a big tank of gravity. It’s not that simple but let’s look at it like that for now. But even from this perspective it’s clear that the tank is not endless. Unless it’s replenished by rain or snow, by evaporation of sea by the sun lifting water back into the mountains, the lake will eventually go dry. In California this is happening right now😢.

This is true of any system that uses gravity to achieve movement or work… skiing, mountain biking, dominoes falling, an apple hitting you on the head. Things will fall until they hit something that stops or supports them, then it takes work to fill the “tank of gravity” back up, to lift them high again. So the falling is really only spending the energy you stored there from some other source.

It’s fun to explore these ideas to get a better handle on how our universe works.


Gravity isn’t a ‘fuel’.
and it isn’t a solution.
𝘉𝘭𝘰𝘤𝘬𝘪𝘯𝘨 gravity as H.G. Wells proposed many decades ago is the solution…


They say this because gravity isn’t energy. Energy cannot be created or destroyed, but only transformed from one form to another. An arrow cannot have more energy than you put into it by pulling back a bowstring. Similarly, a falling rock cannot acquire more energy than it took to lift it in the first place. A spinning disk in a perfect vacuum may spin forever (true perpetual motion), but as soon as you connect it to a gear to do something useful (i.e., work), it starts slowing down as the angular momentum is siphoned away.

I happen to have a bumper sticker on my car (along with my SketchUp badge). This is an old saying that expresses the concept of conservation of energy much more succinctly.

The Greek letters spell out TANSTAAFL … as in There Ain’t No Such Thing As A Free Lunch.


I agree with this 100%, but gravity pulls things down constantly. I believe a pull is energy.
For example, imagine a person arm wrestling an invincible statue. The statue is still, yet the person’s arm is still exerting a force. Compare this to a lamp on a desk. The lamp is still, yet gravity is still exerting a force onto it.

I don’t get why gravity isn’t considered energy.


The energy of a falling domino has lifted one back up. Even if the lever weighed 0 lbs., the weight of the domino would be able to lift the other if the distance was far enough.

Now the problem is the force on one side is multiples of the other side. What if the lever turned into a vertical circular reaction that was able to reset itself with a quarter turn? There could be four levers and each turn could change the fulcrums position. I don’t know…


He means a toppling domino, like the ones you’ve referenced already. Not a domino falling from a distance, where the force of gravity has it and the lever contributing more energy than a single toppling domino could ever achieve. No, a falling domino can’t lift another domino.


Physicists don’t even know the cause of gravity, so how would you know?


The laws of gravity are fully understood. It’s common knowledge. These are tested principles. I know because I studied basic physics in school.