Newton's Third Law broken?

[Phaedrus]

Newton's 3rd law of motion says: For every action there is equal and opposite reaction. This I believe is supposed to make it impossible for a closed system to change its velocity with respect to the ground, for example (or something floating in free space cannot change average velocity without spewing something out or pushing off something else or something like that). But it looks like the Russians have other ideas:

https://www.youtube.com/watch?v=6vmP11Umow0
https://www.youtube.com/watch?v=pcEdpb-rIX4

[For 2nd video, I am talking about 2nd half, not the rotating thingamajig (not sure what that is supposed to show).]

If its this easy to break this "Law", why call it such? Or am I misinterpreting what is going on?

[rlortie]

Take away the electric motor and what do you have?

I have a battery driven clock hanging on the wall that does what we see here!

[Furcurequs]

This sort of behavior is typically due to the difference between static and dynamic friction. There is a stick and slip phenomenon sometimes called "stiction" when there are slow and fast movements in such devices.

Donald Simanek speaks of it on a couple of his web pages:

https://www.lhup.edu/~dsimanek/museum/test-pm.htm
https://www.lhup.edu/~dsimanek/museum/themes/whynot.htm

A better test of these devices would be to see how they behaved while in free fall.

[Wubbly]

wikipedia seems to think they are impossible.

https://en.wikipedia.org/wiki/Reactionless_drive

[Fcdriver]

It seems odd how we each see things differently! I see Newton Law as explaining, not disproving! One weight pushing down can lift 4 @ 1/4 of the way,, one weight can lift 5 @ 1/5 of the way, a equal reaction, does not have to look equal, just be equal! The key to a pm mechanism is for one that can lift 5 lift 4 or 3, to have spare energy! If lifting on the same fulcrum, but using two different fulcrums, where it is the same weight, but at a different distance!

[Tarsier79]

FC. The available lifting energy is determined on Mass x distance of the falling weight. Adding more levers will not help that.

[Fcdriver]

A weight dropping 40 inches will lift five weights 8 inches, these are equal! Fanning the weights 8 inches apart means one will always be reaching the top! Yes there is no additional energy! But only if you are lifting and dropping using the exact same fulcrum point! Nothing says you have to use the exact same fulcrum point!

[Fcdriver]

A class one lever, uses the exact same force, as a class three lever! Nothing keeps you from lifting using a class one lever while dropping using a class three lever, this gives you a different force point, twice the distance of the fulcrum distance from center!

[John doe]

Your only limit is your own imagination....
Don't limit yourself 2d in a 3d world!

[Fcdriver]

the problem comes when dropping the weight 40 inches does not lift the other weights 8 inches each! Some will claim there is a loss of distance! This only means something is not right! The dropping weight has to lift the other weights!

[preoccupied]

For Mother Russia
!

The first video shows a force being created I believe. It should be the same force as I have believed exists with the Chain fountain. When a weight changes direction with greater force, it seems to push its body towards the direction its not swinging. When I've been thinking about the chain fountain and some other ideas like this in my head I view motion as an axle of varying tangibility. I believe there is a tilt by an axle being created somewhere in the force that pushes the body in a direction from movements in a closed system like you are sharing.

If you remember I am talking about this chain fountain. Cambridge University gave an explanation for this Mould Effect but I do not agree with their assumption. I think that instead it's more likely that that Russian video is evidence that the effect is because of motion without external force.
https://www.youtube.com/watch?v=_dQJBBklpQQ

[pequaide]

A one kilogram mass dropped 40 inches will develop 4.464 units of momentum and that is all that will be needed to return it to the top.

A one kilogram mass dropped 40 inches in a 5 kilogram Atwood will develop a velocity of 1.997 m/sec and 9.98 units of momentum.

A one kilogram mass with 9.98 units of momentum will rise 5.076 meters (200 inches).

This transfer of momentum from a large mass to a small mass has been proven and is no longer a matter of debate.

[Fletcher]

A weight dropping 40 inches will lift five weights 8 inches, these are equal!

Fanning the weights 8 inches apart means one will always be reaching the top!

Yes there is no additional energy! But only if you are lifting and dropping using the exact same fulcrum point! Nothing says you have to use the exact same fulcrum point!

the problem comes when dropping the weight 40 inches does not lift the other weights 8 inches each!

Some will claim there is a loss of distance!

This only means something is not right!

The dropping weight has to lift the other weights!

Frank Driver .. here's my input to your above statements that I see appearing again and again.

When a mass drops it loses GPE and gains and equal amount of KE, when there are no frictional loses. This is a linear trade-off of GPE for KE gain. It is purely height dependent since the mass and 'g' are not variables in this scenario.

When you treat the situation you are explaining like an Archimedes Law of Levers problem then you are forgetting something of major importance IMO.

Levers are often explained in text books and in on-line tutorials (e.g Khan Academy comes to mind http://freevideolectures.com/Course/2553/Physics/49 ) as showing the balanced situation which is force times distance etc, where the force is weight force of different masses at different horizontal distances. It is also used to explain why there is no torque because of the balancing of forces.

To get a balanced situation to move e.g F1D2 = F2D1 then you actually have to apply an additional force (could be a small additional mass) to one side or another. Then it is unbalanced and will move downward on that side etc.

However the KE of the masses (plz do not consider the mass of the lever for this thought experiment) is NO greater than the GPE lost of the additional small mass added to one side. The heavier that mass the more velocity and KE's of the F1 & F2 masses.

So my point is simply this. When levers with weights on them move, either up or down, then forces are not balanced. They will accumulate KE which they will retain until they reach a physical limitation such as a stop or the ground etc. Since they have KE then that must come from a conversion of available GPE loss (i.e. NET GPE loss).

[Phaedrus]

This sort of behavior is typically due to the difference between static and dynamic friction. There is a stick and slip phenomenon sometimes called "stiction" when there are slow and fast movements in such devices.

Donald Simanek speaks of it on a couple of his web pages:

https://www.lhup.edu/~dsimanek/museum/test-pm.htm
https://www.lhup.edu/~dsimanek/museum/themes/whynot.htm

A better test of these devices would be to see how they behaved while in free fall.

I wouldn't pay too much attention to Donald Simanek. After all, on that 2nd page you've linked to, he states:

"The fundamental laws of physics do not prohibit perpetual motion."

And we all know that of course perpetual motion is impossible and DOES violate the fundamental laws of physics![/sarcasm]

But all kidding aside, you actually think that there is some kind of friction that is causing the behavior you see in these videos? Really? The friction between the axles of those little wheels and their bearings (in 1st video, I can see that they use ball bearings)? If that is what is going on, then why does the experimenter covering his working surface with oil not change the behavior of the "reactionless_drive" (as Wubbly correctly points out is what we are talking about here) car?

Of course, it would have been a lot more convincing if they had done these experiments on an air-table. Or even better, built a device to do it in 0-gravity and done it on the ISS. But of course, we can't have everything.

I just don't buy that this is due to 'stiction' or whatever you want to call it. I think it is due to a certain kind of friction, though, the friction known as inertia. A mysterious property of matter that we don't really understand.

In fact, I take it back. The reason this happens is because of "stiction". You see, "stiction" is the name they have given to inertia, when it is demonstrated that one of their precious laws of motion is broken. Inertia does tend to impede motion when you try to move a massive object FAST. But it allows motion when you try to move it slowly. But in order to continue to claim that Newton's 3rd law of motion is really a precise LAW of MOTION, they rationalize the type of thing that is going on in these videos by calling it "stiction".

Of course, I could be wrong and this is all just IMHO.

[preoccupied]

We should really try to believe that this could work as propulsion because it would be the fastest form of propulsion available. Other means even magnetic trains with no friction will have boundaries to the means of pushing the carriage. This however will constantly get faster and faster the longer the engine is pumping because new motion will be added to old motion.