Is this contraption theoretically possible?

[Shadow]

https://www.facebook.com/383870055097958/videos/605245652960396/

 

The video is obviously a fake, my guess is that the two black stripes are in fact electromagnets, but frankly I don't really care. What I'm wondering about is, could something like this be constructed, in theory, using a mechanism like this? It goes without saying that it wouldn't display this "periodic" behaviour forever, just apparently so, eventually coming to equilibrium much the same way as a pendulum does (my gut tells me this operates on much the same principle as a pendulum does).

[Bender]

My gut feeling says no, because the hinge should stay up.

[Shadow]

If I understand you correctly, I think you could solve that by designing the contraption so that the velocity of the side with the ball was high enough (when coming down) that you would get the effect seen on the video - or not?

[Bender]

Perhaps. I didn't do the math, nor am I going to invest the time required only to build a worthless gadget.

 

Nevertheless, it might be impossible because the hinge would flip up again before the ball can reach it.

 

Besides, in the video the ball keeps bouncing around, loosing too much energy to keep going for a long time. Even in the ideal case, there is no mechanism to recover the rotational energy of the ball each time it rolls back and forth.

[Delburt Phend]

This guy enjoys making fraudulent machines; but some experiments really do work. See:Hypography “ http://www.scienceforums.com/topic/29662

[Bender]

I can't open your link

[Delburt Phend]

It is probably being blocked; I have an experiment that clearly makes energy and that does not make people happy. They even refuse to receive free videos of it.

[Bender]

So not only are you claiming to have broken the laws of thermodynamics, you are also piling on some conspiracy theories...

 

I'll pass

[Delburt Phend]

I don't think it can be referred to as a conspiracy because it has no single point of organization; it is just a huge mind block; of which your “I will pass” is a prime example. You don't even bother to look at the evidence; you just close your mind to it. These experiments are absolute proof and no one is listening; yet.

[Bender]

I haven't seen any evidence. You haven't even given a schematic of how you would create energy.

 

What I have seen is perhaps hundreds of claims that someone could create free energy, they either refused to provide details, where unable to show evidence, or their theories were easily dismissable with basic science. So all the prior evidence concerning the violation of the laws of thermodynamics suggest that your claim is just one in a long list of exclusively failures.

 

Adding in conspiracy theories about your evidence being blocked, just adds to the idea of you being "yet another crackpot". (with no disrespect, that is just the general category you are putting yourself in)

Edited January 12, 2017 by Bender

[Delburt Phend]

You added the conspiracy theory. The evidence is a de-spin that returns to the original spin. Only linear momentum is conserved in collisions from small to large objects.

[Bender]

Sorry, both angular momentum and energy are also conserved. In fact, the easiest way to predict the outcome of two spinning objects colliding is by using these three conservation laws.

 

Of course, some of the energy will be lost to heat, so now you have effectively lost "useful" energy to entropy.

 

A hint: when attempting to break conservation of energy, at least do the math before making claims. A mundane Newtonian mechanical system will always simply follow Newtonian mechanics (even though the math can be quite challenging at times). If you did the math and got energy out the system: you made a mistake.

 

Only new, hypothetical physics could hope to break conservation laws, because nothing in established physics can.

[Delburt Phend]

F = ma is used to determine how much heat (for energy conservation) is lost. Think about that for a minute; One formula gets it correct and then you add a magic amount of heat to get the other one to be "correct"???

 

Galileo's pendulum proves that angular momentum can't be conserved for one mass on the end of one string.

[J.C.MacSwell]

F = ma is used to determine how much heat (for energy conservation) is lost. Think about that for a minute; One formula gets it correct and then you add a magic amount of heat to get the other one to be "correct"???

 

Galileo's pendulum proves that angular momentum can't be conserved for one mass on the end of one string.

What is the top of the string attached to? Without even doing the math (because let's face it...you haven't)...picture the fixed point unconstrained horizontally

Edited January 13, 2017 by J.C.MacSwell

[Bender]

F = ma is used to determine how much heat (for energy conservation) is lost. Think about that for a minute; One formula gets it correct and then you add a magic amount of heat to get the other one to be "correct"???

 

Galileo's pendulum proves that angular momentum can't be conserved for one mass on the end of one string.

1) F=ma is used to relate force with acceleration. When friction is minimised e.g. in a vacuum or on an air table, the heat losses are negligible and the results are extremely accurate (until relativistic effects starts to play, but that isn't really relevant here).

2) heat losses in mechanical system have been carefully measured, and the loss in mechanical energy matches the increase in heat perfectly. The reverse, where heat is converted to mechanical energy has exactly the same relation. There is no "fumbling" going on as you seem to suggest.

3) please explain how Galileo's pendulum proves that.

 

You still haven't provided a single shred of evidence, or even a clear hypothesis.

[Delburt Phend]

Fix a point horizontally and set up a Galileo pendulum like interaction on both sides simultaneous to eliminate earth motion (does it now do the twist) and you will get the same results. The real motion of the objects remains present: how can the earth absorb motion when the real motion remains. Why is it that F = ma does not need these far fetched excuses. You protect this flawed application of angular momentum; and the error is obvious; there is no gravitational acceleration, which is needed for angular momentum conservation.

 

There are merely two numbers needed to determine angular momentum: you only need linear momentum and radius.

In Galileo’s pendulum: The linear velocity of the bob will be the same one millisecond before and one millisecond after the point when the pendulum string comes in contact with the lower pin. For example: both the before and after velocities could be rounded to 2.00 m/sec. For a one kilogram bob; the before and after linear momentum would be 2.00 units.

The length of the radius just before the pendulum string contacts the lower pin might be twenty meters; and then the radius might be only one meter after the string is in contact with the pin.

So: angular momentum = linear momentum * radius: L = mvr: or 1 kg * 2 m/sec * 20 m = 1 kg * 2 m/sec * 1 m. This is not a conserved quantity: the statement is false. Angular momentum works in space for satellites where gravity changes the linear momentum. Angular momentum conservation does not work in the lab.

 

No they have not found the heat; they do not look for the heat; they don’t even expect to find it. You have too high a view of your people in the world of physics. They can fumble because they have consensus. They require no experiments to support their own concepts.

 

In events like the Dawn Mission despin; the motion of the tethered mass can be returned to the satellite. This is proof that energy is not conserved by the masses on the end of the tether. This is the argument in the site mentioned; but they need to let you view it.

[Bender]

Fix a point horizontally and set up a Galileo pendulum like interaction on both sides simultaneous to eliminate earth motion (does it now do the twist) and you will get the same results. The real motion of the objects remains present: how can the earth absorb motion when the real motion remains. Why is it that F = ma does not need these far fetched excuses. You protect this flawed application of angular momentum; and the error is obvious; there is no gravitational acceleration, which is needed for angular momentum conservation.

 

There are merely two numbers needed to determine angular momentum: you only need linear momentum and radius.

 

In Galileo’s pendulum: The linear velocity of the bob will be the same one millisecond before and one millisecond after the point when the pendulum string comes in contact with the lower pin. For example: both the before and after velocities could be rounded to 2.00 m/sec. For a one kilogram bob; the before and after linear momentum would be 2.00 units.

 

The length of the radius just before the pendulum string contacts the lower pin might be twenty meters; and then the radius might be only one meter after the string is in contact with the pin.

 

So: angular momentum = linear momentum * radius: L = mvr: or 1 kg * 2 m/sec * 20 m = 1 kg * 2 m/sec * 1 m. This is not a conserved quantity: the statement is false. Angular momentum works in space for satellites where gravity changes the linear momentum. Angular momentum conservation does not work in the lab.

 

No they have not found the heat; they do not look for the heat; they don’t even expect to find it. You have too high a view of your people in the world of physics. They can fumble because they have consensus. They require no experiments to support their own concepts.

 

In events like the Dawn Mission despin; the motion of the tethered mass can be returned to the satellite. This is proof that energy is not conserved by the masses on the end of the tether. This is the argument in the site mentioned; but they need to let you view it.

Still waiting for evidence.

A figure would certainly help to clarify your explanations.

 

In the case of measuring heat losses: why not try it yourself? It is not easy to get very accurate results, however, because the system is not entirely closed. As I said, many, many people have tried to find inconsistencies in conservation of energy, none succeeded. You seem to have the wrong idea about what science is: nothing is accepted without (a lot of) experimental evidence.

 

Yo-yo despin: please provide evidence of your claim. To be honest, I'm not really sure what your claim is, so I cannot comment further on it.

[Delburt Phend]

If the weighted tethers are left attached; the original rate of spin is restored to the massive center of the yo-yo de-spin device. This means that the extended weights have linear Newtonian momentum. The energy increase, when the small extended masses have all the motion, is very large.

 

The arc velocity determines the quantity of Linear Newtonian momentum. This has been closely measured and had been confirmed.

[Bender]

If the weighted tethers are left attached; the original rate of spin is restored to the massive center of the yo-yo de-spin device. This means that the extended weights have linear Newtonian momentum. The energy increase, when the small extended masses have all the motion, is very large.

 

The arc velocity determines the quantity of Linear Newtonian momentum. This has been closely measured and had been confirmed.

What do you mean by "the rate of spin is restored"? The point of a despin device is that there is an energy transfer from the centre to the extended weights. There is no energy increase, but a decrease in kinetic energy (the difference goes to heat). Even if you are unable to do the math, you can understand this by sitting on a rotating chair with some weights in your hands: if you have someone rotate you, it takes effort to pull the weights towards you, but letting them stretch your arms is easy.

 

What's up with the blurry picture?

 

Also: evidence, please. Fuzzy ideas aren't evidence.

[Delburt Phend]

https://youtu.be/YaUmzekdxTQ

 

Of the three theories of motion only Linear (arc speed) Newtonian Momentum predicts that the spheres will have enough motion to restore all of the rotational speed back to the cylinder.

 

What you see in the video is the full restoration of motion to the cylinder: twice.

[Bender]

On what basis do you make that claim? I see no violation of conservation of angular momentum or conservation of energy.

 

It would really help if you attempted to do some math. Perhaps that way it would be easier to point out your misconceptions, at least if you are here to learn.

Edited January 19, 2017 by Bender

[Delburt Phend]

This is of course a copy of a yo-yo despin device; I commonly cite the Dawn Mission yo-yo de-spin. For the math I use F = ma: when a small object gives its motion to a larger object only linear Newtonian momentum is conserved. The sphere's mass is 1 / 4.5 the total mass. The total motion is conserved and only linear Newtonian momentum can do this back and forth restoration of motion.

 

Energy conservation would predict large losses; but there are no losses of motion.

[Bender]

Let's calculate the angular momentum in the two extremes (assuming a thin cylinder and small balls with respect to cylinder radius R):

[math]L_1=4.5 R^2 \omega_1[/math]

[math]L_2=2.5 R^2 \omega_{2,cylinder}+2 (R+l_{rope})^2 \omega_{2,balls}[/math]

 

The kinetic energy:

[math]E_1=\frac{4.5 R^2 \omega_1^2}{2}[/math]

[math]E_2=\frac{2.5 R^2 \omega_{2,cylinder}^2}{2}+\frac{2 (R+l_{rope})^2 \omega_{2,balls}^2}{2}[/math]

 

Since angular momentum and energy have to be conserved, we get two equations from which [math]\omega_{2,cylinder}[/math] and [math]\omega_{2,balls}[/math] can easily be calculated:

[math]4.5 R^2 \omega_1=2.5 R^2 \omega_{2,cylinder}+2 (R+l_{rope})^2 \omega_{2,balls}[/math]

[math]\frac{4.5 R^2 \omega_1^2}{2}=\frac{2.5 R^2 \omega_{2,cylinder}^2}{2}+\frac{2 (R+l_{rope})^2 \omega_{2,balls}^2}{2}[/math]

 

Now let's look at the linear momentum:

[math]p_{cylinder}=mv=m \cdot 0=0[/math]

[math]p_{balls}=m_{ball}v_1+m_{ball}v_2=m_{ball}v_1-m_{ball}v_1=0[/math]

As you see, there is no linear momentum. Could you clarify how you would make the calculations with linear momentum if there is no linear momentum?

 

 

note: earlier, I assumed a quasi-static system where the balls are released slowly and remain at the same orientation with respect to the central mass, in that case there is indeed a loss in kinetic energy. There are no significant losses in the system in the video.

Edited January 20, 2017 by Bender

[imatfaal]

!

Moderator Note

 

I have removed Speculative post which seemed to challenge the conservation of angular momentum to the correct forum. Only mainstream physics in the main physic forum please.

 

 

http://www.scienceforums.net/topic/102483-conservation-of-angular-momentum/

[imatfaal]

!

Moderator Note

 

Additional whinge by hijacker also split off - please take it as read that complaints about moderation should not be in the thread.