First of all, I would like to say that this model is NOT a perpetual motion. It will stop eventually. What I want to say here is that the output useful work seems to be greater than input energy

 

My system consists of 2 elements. Each element is a cylinder put on an axle. There are two permanent magnets stuck on each cylinder, with their north poles are faced outside. In the youtube clip that I will show you below, you can see the magnets of the first element are painted in blue, while those of the second one are crossed with X.

 

I turn the cylinders slightly so that the north poles of the magnets are faced each other. Then, the thrust between magnets make the cylinders rotate.

 

A single cylinder on an axle itself is not the system. It is an element of the system, which consists of 2 at all. Therefore, the thrust between magnets is not external force which affect system. It is comprehended as internal force between 2 elements of the system. The thrust from the first cylinder makes the second rotate, and the thrust from the second, in its turn, make the first rotate. Each component act as the cause to make the other rotate, and it acquires the affect from the other to rotate.

 

While the input work of the system originates from a small force making cylinders moving short arc, and make magnets facing each other, the output dynamic energy is much higher. You can see in the clip that both cylinders rotate many circles, which create output useful work much greater than the work to make the magnets facing each other.

 

Here is the link of my clip

http://www.youtube.com/watch?v=GQUPaHE0vCg&feature=youtu.be

 

Your comments are welcomed to determine that if energy conservation is violated in this case or not

Thanks

Thinh Nghiem from Vietnam

In order to make this statement you must have measured (or at least estimated) the input energy.

 

 

You can see in the clip that both cylinders rotate many circles, which create output useful work much greater than the work to make the magnets facing each other.

 

Where do you think the input energy came from?

Say you have a ball attached to a hanging spring. You pull the ball down a bit, then let go. What happens? The ball will oscillate up and down for a while, converting potential energy (which you put into the system when you pulled on the ball) into kinetic energy, then back to potential, then back to kinetic, etc. Your system doesn't violate energy conservation in the same way that the ball on the spring doesn't: you put in some initial potential energy (when you lined up north-north), and the system merely converts potential to kinetic, back to potential, back to kinetic, etc. It will continue to oscillate ("oscillate" is probably the wrong word) like that until it has lost too much energy from friction and air-resistance.

Edited October 20, 201411 yr by elfmotat

First of all, I would like to say that this model is NOT a perpetual motion. It will stop eventually. What I want to say here is that the output useful work seems to be greater than input energy

 

These are contradictory claims. If it worked you could energize a second device, and have some left over. Thus, perpetual motion. Which you don't have.

While the input work of the system originates from a small force making cylinders moving short arc, and make magnets facing each other, the output dynamic energy is much higher.

I think you'll find, with a careful accounting of how much energy you actually did use to initialize the system, that this is not a true statement.

Hi all,

 

1. Initial energy came from he force of my hands to turn the cylinders so that their magnets face each other. If you look into the clip, you can easily see that the cylinders rotate many rounds before stopping, which cause kinetic energy much greater than work made by me

which cause kinetic energy much greater than work made by me

 

Please show that this is the case.

 

Hi all,

 

1. Initial energy came from he force of my hands to turn the cylinders so that their magnets face each other. If you look into the clip, you can easily see that the cylinders rotate many rounds before stopping, which cause kinetic energy much greater than work made by me

 

 

How did you measure this?

 

Hi all,

 

1. Initial energy came from he force of my hands to turn the cylinders so that their magnets face each other. If you look into the clip, you can easily see that the cylinders rotate many rounds before stopping, which cause kinetic energy much greater than work made by me

 

That is where you are wrong,after a few seconds (YT = 50 seconds) all the energy has gone out of the system.

 

1. Initial energy came from he force of my hands to turn the cylinders so that their magnets face each other. If you look into the clip, you can easily see that the cylinders rotate many rounds before stopping, which cause kinetic energy much greater than work made by me

 

 

 

Well yes and no.

 

Yes the energy came from your hands.

And yes you input a small amount of energy turning the spinners.

 

But no that was not all the energy you input.

 

You have two magnets and it takes energy to bring them from a large separation to the close proximity you show on their pivots.

 

Calculate this and you will find it is the bulk of the energy input, so there is no violation of conservation.

 

Thank you for the video.

If I throw a super ball at the ground, it will bounce up to several times the height it started from and bounce a large number of times before coming to a rest.

 

If I flick a crumb off my desk with my finger, I only push it for an inch or so but then it flies all the way across the room.

 

The problem isn't that the system is outputting more than you put in. It's that you are making a false equivalence between the motion of the system as you are putting in the energy and the freely moving system after you've released it.

 

 

Well yes and no.

 

Yes the energy came from your hands.

And yes you input a small amount of energy turning the spinners.

 

But no that was not all the energy you input.

 

You have two magnets and it takes energy to bring them from a large separation to the close proximity you show on their pivots.

 

Calculate this and you will find it is the bulk of the energy input, so there is no violation of conservation.

 

Thank you for the video.

 

Hi Studiot,

 

I see your idea. My comparison goes with the input and output energy of the system. I know the thrush between magnets, but I consider it as INTERNAL interaction between two components of the system, not the external energy outside, so I do not involve it here.

 

I have plan to improve my model so that it can rotate longer, for example 1 hour. Do you think it is economical. It can be used in a rotor of a generator. We do not need fuel, just our manual force, and the rotor will spin for a long time to generate current. Is it OK?

It's still only the force you manually put in there. You could be turning a crank with your hands and it would be WAY more efficient. We are still waiting for your kinetic calculations btw.

I have plan to improve my model so that it can rotate longer, for example 1 hour. Do you think it is economical. It can be used in a rotor of a generator. We do not need fuel, just our manual force, and the rotor will spin for a long time to generate current. Is it OK?

 

But as soon as you connect it to a generator to extract energy it will grind to a halt immediately.

 

But as soon as you connect it to a generator to extract energy it will grind to a halt immediately.

Not if you extract the energy really, really slowly and in very small amounts!

Not if you extract the energy really, really slowly and in very small amounts!

Was that just a play on words? Lengthening "immediately" to a little longer but still inevitably stopped.

Unfortunately this forum won't allow copy and paste of quote with a bog standard windows 7 system, fully up to date by \Microsoft standards.

 

So I can't quote from your post#12

 

However you may rest assured that the you could not bring two magnets close together without inputting energy (in the form of work) to the system.

So you cannot choose to discount or ignore this energy in your accounting.

 

It really is that simple.