John2020 Posted May 22, 2021 Author Posted May 22, 2021 (edited) 25 minutes ago, swansont said: The ring’s vibrations cause the table to vibrate. This is an action-reaction force from Newton’s 3rd law. The table is, as you note, an external component. We agree on something, at least. Yes, the ring vibrates that causes the vibration of the table. So you accept there is a force coming from inside the ring. 25 minutes ago, swansont said: So: force exerted by the table causes the ring to accelerate (in accordance with Newton’s 1st and 2nd laws) That would be true, if the force was not coming from inside the ring. I mean if an external force was pushing the ring by putting its "feet" on the table (base on Action-reaction principle). In our case the force comes from inside the ring. So, according to Newton's 2nd and 3rd law, the motion of the system cannot be justified. Exp #1 (moving across the table) is actually more complicated therefore, please revisit the About Me section of my profile and watch the Exp #2 (LEGO car) and then Exp #3 rotating ring where its rotation is manually controlled by applying a frequency shift (increasing frequency -> clockwise rotation, decreasing frequency -> counterclockwise rotation). If you agree the vibration of the ring or the vibration of a rotating unbalance is caused by a force that comes from inside the system then, Newton's 2nd and 3rd law cannot justify the vibration itself (action-reaction in the context of internal forces). In order to justify vibration by means of internal forces then, in the case of the rotating unbalance, a momentum transfer should have taken place from the eccentric to the rest of the system. But even so, Newton's 3rd law wouldn't allow the system to vibrate. 25 minutes ago, swansont said: No, when you set k to zero you will not have oscillations. Then set it to a value close to zero, it is irrelevant. It is used to calculate the vibration frequency, however this is a passive component and not associated with the excitation force (which is the main cause behind the motion of the rotating unbalance system). Without excitation force (centripetal) there wouldn't be vibration (or better motion in one direction and then on the other). Edited May 22, 2021 by John2020
swansont Posted May 22, 2021 Posted May 22, 2021 24 minutes ago, John2020 said: That would be true, if the force was not coming from inside the ring. I mean if an external force was pushing the ring by putting its "feet" on the table (base on Action-reaction principle). In our case the force comes from inside the ring. So, according to Newton's 2nd and 3rd law, the motion of the system cannot be justified Bollocks. The ring is vibrating, so it is not a rigid mass. Your analysis would mean a person couldn’t jump upward, because there’s a force that comes from inside the person. Which should clearly be the wrong conclusion. You can jump, and this doesn’t violate the laws of motion. (the real ones, not your version of them)
John2020 Posted May 22, 2021 Author Posted May 22, 2021 When we set the stiffness to zero we will have no vibrations reflected back to a surface where the system was touching previously but we will still have vibration of the system due to the rotation of the eccentric mass.
swansont Posted May 22, 2021 Posted May 22, 2021 24 minutes ago, John2020 said: Without excitation force (centripetal) there wouldn't be vibration (or better motion in one direction and then on the other). Excitation force is something you made up, so stop it, and this has nothing to do with the centripetal force. 1 minute ago, John2020 said: When we set the stiffness to zero we will have no vibrations reflected back to a surface where the system was touching previously but we will still have vibration of the system due to the rotation of the eccentric mass. You don’t accept the underlying physics as being correct, so this is pointless, is it not? And there’s no eccentric mass. Leave your other threads out of it.
John2020 Posted May 22, 2021 Author Posted May 22, 2021 (edited) 1 hour ago, swansont said: Excitation force is something you made up, so stop it, and this has nothing to do with the centripetal force. I didn't make up anything. See the differential equation I shared previously. No angular velocity leads to no centripetal force, consequently no vibration. Since the differential equation engages forces, the centripetal can be considered as the excitation force (Setting this to zero, no vibration will ever occur). 1 hour ago, swansont said: Bollocks. The ring is vibrating, so it is not a rigid mass. Your analysis would mean a person couldn’t jump upward, because there’s a force that comes from inside the person. Which should clearly be the wrong conclusion. You can jump, and this doesn’t violate the laws of motion. (the real ones, not your version of them) You are comparing apples with oranges. A person may jump upwards because his body may contract and then suddenly expand by taking advantage the change of its center of gravity and the normal force originated by the floor. In outer space this couldn't happen, meaning to self-propel himself by contracting/expanding the body or by being suspended by a thread and under the influence of gravity however without touching the floor and attempting to contract/expand the body. Here we have a typical example of an action-reaction pair created by external forces (normal (floor) and gravitational force exerted on the center of gravity of the person). In this example the forces are rectilinear something that does not seem to apply in the case of a rotating unbalance (it is easier to refer to a mechanical construction than the experiment (electromagnetic device) in order to justify the cause behind the vibration). 1 hour ago, swansont said: You don’t accept the underlying physics as being correct, so this is pointless, is it not? And there’s no eccentric mass. Leave your other threads out of it. Nobody said that the underlying physics is not correct. Shouldn't we no comment when something is not justified when we describe the behavior of a system? Have you ever raised your hand in a class room? I don't understand what is your problem. I use arguments and observations based on the established physics. Now since the experiments I conducted are based on a pure electromagnetic device, it is somehow difficult to justify the behavior of the system therefore, I frequently refer to the rotating unbalance thread. Right, we leave the other threads out but please focus on Exp #2 (LEGO car) and Exp #3 (controllable rotating ring). Check the About Me section in my profile. Again, Exp #1 is more complicated that means more controversial, so let it at the moment out of this discussion. How do you justify the motion of the LEGO car and the controllable rotation of the ring by utilizing a frequency shift? Edited May 22, 2021 by John2020
swansont Posted May 22, 2021 Posted May 22, 2021 40 minutes ago, John2020 said: I didn't make up anything. See the differential equation I shared previously. No angular velocity leads to no centripetal force, consequently no vibration. Since the differential equation engages forces, the centripetal can be considered as the excitation force (Setting this to zero, no vibration will ever occur). This makes zero sense. Quote You are comparing apples with oranges. A person may jump upwards because his body may contract and then suddenly expand by taking advantage the change of its center of gravity and the normal force originated by the floor. Contract and expand, while we have a piece of metal expanding and contracting because of a changing magnetic field. Yeah, nothing similar at all, except for the expanding and contracting. Quote In outer space this couldn't happen, meaning to self-propel himself by contracting/expanding the body or by being suspended by a thread and under the influence of gravity however without touching the floor and attempting to contract/expand the body. We’re not looking at an example in outer space, so this is just another non-sequitur Quote Here we have a typical example of an action-reaction pair created by external forces (normal (floor) and gravitational force exerted on the center of gravity of the person). The reaction force to the normal force of the floor on the person is the normal force the person exerts on the floor. Quote In this example the forces are rectilinear something that does not seem to apply in the case of a rotating unbalance (it is easier to refer to a mechanical construction than the experiment (electromagnetic device) in order to justify the cause behind the vibration). The example for this thread is not an issue of a rotating unbalanced system. 50 minutes ago, John2020 said: I use arguments and observations based on the established physics You claim behavior can’t be explained and that Newton’s laws are being violated. That’s the opposite of established physics. 52 minutes ago, John2020 said: Now since the experiments I conducted are based on a pure electromagnetic device But it’s not, since magnetostriction couples the EM to mechanical motion.
Phi for All Posted May 22, 2021 Posted May 22, 2021 54 minutes ago, John2020 said: I use arguments and observations based on the established physics. ! Moderator Note You've been shown several times exactly where this isn't so, and haven't commented, other than hand-waiving denials. You've ignored reasoned objections to your arguments, calling them apple/orange comparisons. You've insisted on linking offsite instead of pasting info here and following the rules you agreed to when you joined. This is a science discussion forum. It's not peer review, but in order to invest some meaning into our conversations, we require more rigor than you're currently willing to give us. Please take some time off and see if you can address this deficit within the parameters of the rules.
exchemist Posted May 22, 2021 Posted May 22, 2021 3 hours ago, John2020 said: I shared the above as a reply to swansont regarding that internal forces are the cause of vibration (we speak always for the experiments and the similarity with a rotating unbalance) where the differential equation cannot justify (I think this is very clear, although you tend to ignore it). Your blender vibrates because it is a rotating unbalance and not a vibrating string with a mass attached. In absence of gravity, it would have the same behavior (vibrating). You still have the focus on Exp #1, which is more complicated I would say. Please revisit the About me section of my Profile and watch the LEGO car (Exp #2) and the rotating ring (Exp #3) videos. Those two experiments have nothing to do with your claims above. Especially, the rotating ring (Exp #3) where the rotation is controlled by manually shifting the excitation frequency (increasing frequency -> clockwise rotation, decreasing frequency -> counterclockwise). This seems to be incoherent rubbish. I'm off to bed.
John2020 Posted May 25, 2021 Author Posted May 25, 2021 @Phi for All Thank you that you suspended my count for two days. This gave me the chance to rethink all these (as you correctly advised me) and reread the comments of all participants. I will address all comments I ignored (by mistake or by speed or by ignorance) so far one by one. However, I will do this later on the day (in about 8 hours from now) if the thread will be still on the air. In the meantime to anyone who would like to add something in this discussion and since the rules do not allow to use links for a discussion, please visit the About Me section of my profile to watch the material under discussion. Somewhere in the guidelines threads as the "So you've got a new theory", @swansont writes "Evidence is the king". I wonder, whether an Author is wrong or not, why the forum does not allow an evidence (whether true or not will be proved in the discussion, if possible) like a video clip with some home made experiments to be used as the basis material for this discussion? I don't find this right ( and not only me ). Think about it.
swansont Posted May 25, 2021 Posted May 25, 2021 1 hour ago, John2020 said: why the forum does not allow an evidence (whether true or not will be proved in the discussion, if possible) like a video clip with some home made experiments to be used as the basis material for this discussion? I don't find this right ( and not only me ). Think about it. We have thought about it. Not everyone can watch a given video for various reasons, and they should not be shut out of the discussion. Videos can’t be quickly scanned like written material, so it’s an unreasonable investment of time (especially since videos follow Sturgeon’s law) Videos can’t be easily quoted. And too many people would (and have) posted only to drive traffic to their channel. The evidence really isn’t the issue here. Nobody has tried to argue that there isn’t motion. That you have insisted on things that are contrary to Newton’s laws of motion is the issue. Complaining about not being able to post a video link is a red herring, distracting from your misunderstanding and misrepresentation of physics. IOW: it’s not the evidence, it’s your erroneous conclusions. 2
Ghideon Posted May 25, 2021 Posted May 25, 2021 (edited) On 5/22/2021 at 1:00 PM, John2020 said: a) Since there are no external forces pushing the ferromagnetic ring in any direction in all three videos then, how does it move? b) if (a) is correct then, what Newton's 3rd law has to say about it? We know from established physics that "inertial drives" are not physically possible, hence any acceleration of the COM of the ferromagnetic ring is due to external forces; very simplified: F=ma. Note that Newton's laws exists in a framework of more fundamental theories and models developed later. Lagrange, Hamilton and Noether are specifically relevant in this case. If you believe space to be inhomogeneous or anisotropic at small scales please provide evidence. Edited May 25, 2021 by Ghideon grammar, format 1
exchemist Posted May 25, 2021 Posted May 25, 2021 2 hours ago, Ghideon said: We know from established physics that "inertial drives" are not physically possible, hence any acceleration of the COM of the ferromagnetic ring is due to external forces; very simplified: F=ma. Note that Newton's laws exists in a framework of more fundamental theories and models developed later. Lagrange, Hamilton and Noether are specifically relevant in this case. If you believe space to be inhomogeneous or anisotropic at small scales please provide evidence. To put it another way, we know @John2020's (a) is not correct.............because of Newton's laws. @John2020 does not seem to realise they are so well established that the first thing we do in analysing a mechanical system is to apply them and see what they tell us. So the logic is that the ring starts to move, ergo there is an external force responsible. It is then just a matter of identifying how that force arises. 1
swansont Posted May 25, 2021 Posted May 25, 2021 Most people see a conflict between their observation and their understanding of physics, and conclude their understanding is flawed. These folks would look at the explanations and gain understanding. A few others see this conflict, and conclude the laws of physics are wrong. John2020 is not the first, and will not be the last, to take this stance here. But there’s no traction to it. The laws of physics are not wrong. The extra frustration is that this is a fairly trivial case and the misunderstanding is of such a fundamental concept. There’s no effort to gain anything, because of the denial that their understanding is flawed. 2
John2020 Posted May 25, 2021 Author Posted May 25, 2021 @swansont, @exchemist, @Ghideon, my main problem or lack of understanding is derived from the following reasoning: (1) From the moment Newton’s laws are correct, could one show me where we may find the external action force being responsible for the horizontal motion of the system (ring)? If one of you has already mentioned this, please repeat it. (2) According to Newton’s 3rd law, the action force being exerted upon the table should create a reaction force from the table towards the ring that will push the latter forward. (3) The external action force we are looking for (or better in order to justify the motion of the system according to Newton’s laws of motion) should be horizontal, otherwise system’s motion cannot be justified (especially the one with the LEGO car and the other with the controllable rotation of the ring). (4) The LEGO car case has three issues that need to be addressed: a) where we may find the external action force, b) where we may find the external reaction force and c) according to Newton’s 3rd law the system LEGO car + ring shouldn’t move at all, contrary to what we witness. We know that nobody (e.g. ring) is able to push his own car (e.g. LEGO car) while being inside and this is explained by Newton’s 3rd law in the context of internal forces (the net work done by internal forces is zero therefore, system motion cannot occur).
swansont Posted May 25, 2021 Posted May 25, 2021 6 minutes ago, John2020 said: (1) From the moment Newton’s laws are correct, could one show me where we may find the external action force being responsible for the horizontal motion of the system (ring)? If one of you has already mentioned this, please repeat it. The (vibrating) table exerts a force on the ring. But you didn’t miss this: Quote (2) According to Newton’s 3rd law, the action force being exerted upon the table should create a reaction force from the table towards the ring that will push the latter forward Yes Quote 3) The external action force we are looking for (or better in order to justify the motion of the system according to Newton’s laws of motion) should be horizontal, otherwise system’s motion cannot be justified (especially the one with the LEGO car and the other with the controllable rotation of the ring). Not looking for. Found. You keep acting like the table isn’t there, which is ridiculous.
John2020 Posted May 25, 2021 Author Posted May 25, 2021 1 minute ago, swansont said: The (vibrating) table exerts a force on the ring. But you didn’t miss this: 1 minute ago, swansont said: Not looking for. Found. You keep acting like the table isn’t there, which is ridiculous. If it was so clear I wouldn't have opened this thread. I think you are confusing the action with the reaction. The reaction comes from the table towards the ring in the case of a action-reaction pair of external forces. In order to have a reaction there has to be an external action. Where is it? It cannot be originated other than the ring itself. So the next logical question is, what is the cause of ring's vibration? Is it caused by an internal or external effect? Is the magnetostrictive strain effect internal to the ring or external? From my understanding the magnetostrictive strain effect is internal therefore, internal forces may not be transferred outside the ring. In other words, internal momentum cannot be transferred outside the ring. Where am I wrong on the above?
exchemist Posted May 25, 2021 Posted May 25, 2021 (edited) 28 minutes ago, John2020 said: If it was so clear I wouldn't have opened this thread. I think you are confusing the action with the reaction. The reaction comes from the table towards the ring in the case of a action-reaction pair of external forces. In order to have a reaction there has to be an external action. Where is it? It cannot be originated other than the ring itself. So the next logical question is, what is the cause of ring's vibration? Is it caused by an internal or external effect? Is the magnetostrictive strain effect internal to the ring or external? From my understanding the magnetostrictive strain effect is internal therefore, internal forces may not be transferred outside the ring. In other words, internal momentum cannot be transferred outside the ring. Where am I wrong on the above? You are wrong in asserting that " internal forces may not be transferred outside the ring", if the ring is in contact with something external. If you jump up and down on the spot, your muscles exert purely internal forces on the bones of your legs, causing them to extend. If you were not in contact with the ground, nothing would happen. But you are in contact with the ground, so as your legs try to extend they press on the ground and the reactive force from the ground pushes you up. We have already explained why the AC current makes the ring vibrate. What is a vibration? It is a repetitive up and down motion. So exactly analogous to your legs when you jump on the spot. The ring is in contact with the table so every downward motion of the vibration makes the ring jump up in reaction. The motion then changes to an upward one, but the ring is how higher off the table than it was before, so it is free of the table for an instant. There is thus a point in each vibration cycle at which the ring has jumped off the table and is free to move in response to any tiny force. We can get onto that in a minute, but first, do you now understand how a vibrating ring in contact with a table experiences varying forces from it? If you still can't understand this point, we can't move on to the rest of it. Edited May 25, 2021 by exchemist
swansont Posted May 25, 2021 Posted May 25, 2021 37 minutes ago, John2020 said: If it was so clear I wouldn't have opened this thread. I think you are confusing the action with the reaction. The reaction comes from the table towards the ring in the case of a action-reaction pair of external forces. In order to have a reaction there has to be an external action. Where is it? It cannot be originated other than the ring itself. Action and reaction forces are both forces, so it doesn’t matter if it’s one or the other. Objects accelerate because a force acts on them. They don’t care if it’s an action force or a reaction force. The ring exerts a force on the table. The table exerts a force on the ring. As described by the 3rd law. 37 minutes ago, John2020 said: So the next logical question is, what is the cause of ring's vibration? Is it caused by an internal or external effect? Is the magnetostrictive strain effect internal to the ring or external? From my understanding the magnetostrictive strain effect is internal therefore, internal forces may not be transferred outside the ring. In other words, internal momentum cannot be transferred outside the ring. Where am I wrong on the above? We’ve covered the cause of the vibration. Your claim that internal forces can’t transferred outside is false; you already acknowledged that a person can jump in the air. (and if you now assert that one cannot, there is no point in further discussion)
John2020 Posted May 25, 2021 Author Posted May 25, 2021 5 minutes ago, exchemist said: We can get onto that in a minute, but first, do you now understand how a vibrating ring in contact with a table experiences varying forces from it? If you still can't understand this point, we can't move on to the rest of it. 1 minute ago, swansont said: The ring exerts a force on the table. The table exerts a force on the ring. As described by the 3rd law. This is exactly the point for me that is difficult to justify in terms of Newton's laws of motion. Since the force is internal then due to the action-reaction principle the ring shouldn't vibrate at all (the net work of internal force is zero) therefore, it should not transfer momentum to the table, contrary to what we witness. Consequently, does it vibrate because it is within a gravitational field that acts as the external force upon the center of gravity of the system (ring)? -1
exchemist Posted May 25, 2021 Posted May 25, 2021 (edited) 4 minutes ago, John2020 said: This is exactly the point for me that is difficult to justify in terms of Newton's laws of motion. Since the force is internal then due to the action-reaction principle the ring shouldn't vibrate at all (the net work of internal force is zero) therefore, it should not transfer momentum to the table, contrary to what we witness. Consequently, does it vibrate because it is within a gravitational field that acts as the external force upon the center of gravity of the system (ring)? This is now so garbled as to be impossible to tease apart and correct. Almost every word is wrong or meaningless in the context in which it appears. Are you now really now claiming that Newton's laws say the ring can't vibrate, in spite of all the previous explanations? Edited May 25, 2021 by exchemist
swansont Posted May 25, 2021 Posted May 25, 2021 6 minutes ago, John2020 said: This is exactly the point for me that is difficult to justify in terms of Newton's laws of motion. Since the force is internal then due to the action-reaction principle the ring shouldn't vibrate at all (the net work of internal force is zero) therefore, it should not transfer momentum to the table, contrary to what we witness. Consequently, does it vibrate because it is within a gravitational field that acts as the external force upon the center of gravity of the system (ring)? Why do you think a coil of wire exerting a magnetic force on the ferrite ring is an internal force in the ring? Work and momentum are nit the same thing, and I would be interested to know exactly where you got the “the net work of internal force is zero“ idea? It’s fairly obvious that you should examine the simplest system possible to clear up your misconceptions, but that’s not been your MO. Having three different misconceptions all colliding in an example makes this much more difficult. Plus the attitude that Newton is wrong, not you.
DanMP Posted May 25, 2021 Posted May 25, 2021 9 minutes ago, John2020 said: In order to have a reaction there has to be an external action. Where is it? ... I think the best answer until here was the one exchemist offered: Quote OK. So you have a high frequency alternating magnetic field in this ferrite ring, and when you energise it you find the ring slowly slides across the table. I notice the table has metal legs and that there are various large metal components also on the table. It is unclear whether or not the table is flat. I have two questions for you. First, if you hold the ring in your hand, do you feel any vibration, or when it is on the table, can you hear any sound from it? Second, what happens when you place the ring on a surface with no metal objects nearby? So, the vibration that makes the friction with the table almost zero is from the "high frequency alternating magnetic field". You wrote "Driving Frequency approx. 5 KHz". See here that the sound/vibration in your videos has about 5 kHz. The external force that causes the slide may be gravitational (you didn't show with a bubble level meter that the table is perfectly horizontal) or/and magnetic ("I notice the table has metal legs and that there are various large metal components also on the table").
John2020 Posted May 25, 2021 Author Posted May 25, 2021 2 minutes ago, exchemist said: This is now so garbled as to be impossible to tease apart and correct. Almost every word is wrong or meaningless in the context in which it appears. Are you now really now claiming that the ring can't vibrate, in spite of all the previous explanations? 3 minutes ago, swansont said: Why do you think a coil of wire exerting a magnetic force on the ferrite ring is an internal force in the ring? Work and momentum are nit the same thing, and I would be interested to know exactly where you got the “the net work of internal force is zero“ idea? No, you misunderstood me. I presented a reasoning. When the cause of vibration comes from internal forces then the system (ring) should be able to move or vibrate due to Newton's 3rd law. It is Newton's 3rd law that does not allow motion by means of internal forces, not me. Regarding the net work of internal forces, it is clear the net work of internal forces (since it is zero) cannot trigger system's motion. Everybody knows this. It is derived by Newton's 3rd law: ΣW = WA + WR = 0 (work of action pus the work of reaction equals zero).
swansont Posted May 25, 2021 Posted May 25, 2021 3 minutes ago, John2020 said: Newton's 3rd law that does not allow motion by means of internal forces, not me. No, that’s not correct. You do not understand the 3rd law, and therefore misrepresent it. 3 minutes ago, John2020 said: Regarding the net work of internal forces, it is clear the net work of internal forces (since it is zero) cannot trigger system's motion. Everybody knows this. It is derived by Newton's 3rd law: ΣW = WA + WR = 0 (work of action pus the work of reaction equals zero). Action and reaction forces act on different bodies, so it’s nonsensical to do this math. It’s like saying energy is conserved, so nothing can move.
John2020 Posted May 25, 2021 Author Posted May 25, 2021 Just now, swansont said: No, that’s not correct. You do not understand the 3rd law, and therefore misrepresent it. I don't understand what you mean here? I consider the ring as an isolated system being influenced only by the internal magnetostrictive strain that means an isolated system powered by internal forces, according to Newton's 3rd law will never acquire a momentum. It is the same when one tries to lift himself by its hair or pushing a car while being inside (see LEGO car with the ring).
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