Zet Posted January 24, 2015 Posted January 24, 2015 A magnet is demagnetized. In a closed system there is a ferromagnet and two chemicals in a packet nearby. If the chemicals are exposed to one another thermal energy is generated. (There will be a decrease in chemical potential energy and an equal increase in thermal energy.) The increase in temperature will be enough to raise the ferromagnet above its Curie temperature. (There are no other strong magnetic fields nearby.) EN1 The chemicals are exposed to one another and the temperature increases. The ferromagnet becomes demagnetized. The demagnetized state is a higher energy state than the magnetized state. EN2 There is a decrease in chemical potential energy. There is an increase in thermal energy. And there is an increase in energy in the form of demagnetization. And so, for energy to be conserved, in the end, the increase in thermal energy must be less than the decrease in chemical potential energy. The decrease in chemical potential energy must equal the increase in thermal energy plus the increase in energy in the form of demagnetization. When the ferromagnet goes from magnetization to demagnetization there must be an equal decrease in thermal energy for energy to be conserved (... since there are no other energy change options in this system). [Does anyone have a site showing this is true or not?] Now, two magnetically aligned magnets are close to one another but some distance apart. There is a certain amount of potential energy between them. The packet of chemicals is closer to one of the magnets than the other. The chemicals are exposed to one another, and one of the two magnets is demagnetized. There was a certain amount of potential energy between them due to mutual attraction, and now there is no potential energy between them due to mutual attraction. (The magnets are far enough away from one another so that the magnetic field of the non-demagnetized magnet is not strong enough to keep the other magnet magnetized, but not so far so that there isn’t some (even if a very tiny) attraction between the two magnets before the demagnetization.) The magnets are in one another’s magnetic field. EN3 When the one magnet is demagnetized, it is immediately cut off from the magnetic field of the other. While for the other non-demagnetized magnet, it may take some time (at the speed of light or less, presumably) for it to then be cut off from the magnetic field of the already demagnetized magnet even though it has already been demagnetized. (And, at the most, or at the earliest, the other non-demagnetized magnet is cut off from the mutual attraction at the same instant the demagnetized magnet is.) All of the same energy changes occur as when there was with just one magnet, but with two magnets there is also one additional energy change. There is a decrease in chemical potential energy. There is an increase in thermal energy. There is an increase in energy in the form of demagnetization. And there is a change in the amount of potential energy due to mutual attraction between the two magnets. And so, for energy to be conserved, in the end, the decrease in chemical potential energy must equal the increase in thermal energy plus the increase in energy in the form of demagnetization ... plus or minus (or neither) the change in potential energy between the two magnets due to their loss of mutual attraction (depending on how the potential energy between them in this situation is defined). (If the potential energy between them due to mutual attraction is positive then there needs to be an additional decrease in thermal energy, if the potential energy between them due to mutual attraction is negative then there needs to be an additional increase in thermal energy, and if the amount of potential energy between them is 0 then there needs to be no change in the amount of thermal energy, to then offset the change (or no change) in the potential energy between them due to the loss of mutual attraction.) EN4 The same thing is done again, but this time, from the other side. The same dynamics will occur in the inverse. And, so, the same conservation of energy analysis applies. Now, it is done again for the third time, but this time the two magnets are simultaneously demagnetized. At the moment of each magnet’s demagnetization each magnet is immediately cut off from the magnetic field of the other. This lack of mutual attraction then makes its way back across the distance of the field, but the other magnet has also already been cut off from the magnetic field and so is already in the state of lack of mutual attraction. When one of the magnets is demagnetized it is instantly cut off from the shared magnetic field and so whether the other magnet is demagnetized at the same time or whether it remains magnetized is immaterial the demagnetized magnet (or magnets). When only one of the two magnets is demagnetized, for energy to be conserved, the decrease in chemical potential energy must equal the increase in thermal energy plus the increase in energy in the form of demagnetization ... plus or minus (or neither) the change in potential energy between them due to their mutual attraction. And since whether or not the other magnet remains magnetized or is simultaneously demagnetized is immaterial (due to the demagnetized magnet or magnets being cut off from the magnetic field at the instant of its own demagnetization), then the same energy changes physically must occur with each magnet regardless of the status of the other magnet (whether still magnetized or simultaneously demagnetized). So, whether or not the other magnet is simultaneously demagnetized, with each magnet and each packet of chemicals, there is initially an equal increase in thermal energy as there is a decrease in chemical potential energy. But upon the instance of demagnetization, with each magnet, there must be a decrease in this otherwise increased thermal energy to offset the increased energy in the form of demagnetization. And, with each magnet, simultaneously demagnetized or not, there must be an increase or a decrease (or neither) in another form of energy (such as thermal energy) to offset the change in potential energy due to the loss of mutual attraction between the magnets. (Again, whether the other magnet remains magnetized or is simultaneously demagnetized is immaterial.) When one magnet was demagnetized, the loss of mutual attraction, and the potential energy that goes with that, between the two magnets must be accounted for with energy changes with the one demagnetized magnet alone (... there are no other energy change options). But, since upon the instance of demagnetization whether the other magnet remains magnetized or not is immaterial, whatever physical process one demagnetized magnet goes through when the other is not must be the same physical process each magnet goes through when each magnet is demagnetized while the other is also simultaneously demagnetized (... since the magnetized or not magnetized state of the other magnet is immaterial upon the instance of demagnetization). But this means when the two magnets are simultaneously demagnetized the offsetting energy change for the change in the potential energy due to mutual attraction between them occurs twice (once for each magnet) while the actual change in the potential energy between them due to mutual attraction only occurs once in physical reality. And so, the logic required to find energy is conserved in the first scenario (there is a change in thermal energy with the one demagnetized magnet that offsets the full change in potential energy between the two magnets due to the loss of mutual attraction), then (sense the same physical process must occur in both cases given that the magnetization or not status of the other magnet is immaterial) including this same physical process in the second scenario (there is the same change in thermal energy with each magnet simultaneously demagnetized; while only one of these two changes alone would have offset the total amount of change in potential energy between them) means energy is not conserved in this second scenario. With one exception, maybe. If the amount of potential energy between the two magnets due to mutual attraction is set to 0 at the time of either of one of the two magnets’ demagnetization, then 0 amount of potential energy becomes no potential energy in both the one demagnetized and in the both simultaneously demagnetized cases. And so, in a sense, energy is conserved. (And it just takes a moment for this new reality to make its way to the non-demagnetized magnet in the one demagnetized case while not (but rather instantaneous for both) in the simultaneously demagnetized case.) But this, at the very least, seems like somewhat of a dodge. There is 0 amount of potential energy between them before demagnetization in the sense of in relation to other amounts of potential energy. It is not that 0 amount of potential energy is no potential energy. There was some amount (even if 0 amount) of potential energy before the demagnetization and then that existent energy (whatever amount) is gone. And, even if this somewhat of a dodge works, it only works if there is only one set of magnets. If there are two sets of magnets in the same closed system, and if the distance between the two in each set is different, then this somewhat of a dodge doesn’t work. Only one set can be designated as 0 amount of potential energy between them, which necessarily means the amount of potential energy between the two in the other set is either a positive or negative amount of energy. And so, with a non-zero amount of potential energy between at least the two magnets in of one of the sets, the change in this positive or negative energy between them cannot both lead to energy conserved in the two cases where, one, the other magnet (in this set) remains magnetized and where, two, the other magnet (in this set) is simultaneously demagnetized. The conservation of energy analysis issue is not yet resolved. ? --- (The only other thing I can think of is that in the case where only one magnet is demagnetized, the retreating field lines retreating towards the still magnetized magnet, somehow cause the still magnetized magnet to change energetically in a way that does not occur when they are both cut off from the field simultaneously and so do not encounter the retreating field lines of the other and thus don’t have the same energy change, but it’s hard for me to see a path back to conservation of energy via this route. ? ) --- EN1: A ferromagnet spontaneously magnetically aligns itself within itself when below a certain temperature, while becomes magnetically disaligned within itself when above this temperature, unless there is another strong magnetic field nearby to keep the heated ferromagnetic still magnetically aligned. EN2: It is understood that the magnetic dipoles within the ferromagnet will spontaneously magnetically align unless there is a change, such as in increase in thermal energy, which then places them into a state of misalignment; thus making the demagnetized state (as opposed to the magnetized state) the higher energy state. EN3: The U shaped magnetic field lines were meant to be simple symbol of the retreating field lines. A more accurate drawing would have used oval field lines. A more accurate drawing would have included the straight field lines from one pole on each magnet to the two opposite poles on each magnet. And a more accurate drawing would have also included the field lines from each of the two magnets that are out and away from one another on their other sides. EN4: One of these three energy options must occur while the other two do not and so, upon physical experimentation, this (the actual amount of potential energy present between the two magnets due to mutual attraction) is no longer a matter of stipulation. However, this discussion here occurs before physical experimentation. This is part of the “forming a hypothesis” stage where one’s logic must work out within itself when forming that hypothesis about the physical world.
John Cuthber Posted January 24, 2015 Posted January 24, 2015 " The demagnetized state is a higher energy state than the magnetized state." I doubt that. Given time a magnet will slowly lose it's magnetism.
MigL Posted January 24, 2015 Posted January 24, 2015 Not another 'missing potential energy' question ?!?! The two systems are different. It takes a certain amount of energy to 'randomize' all the tiny magnetic domains in the single magnet. If a second magnet is present, its field will act on the first magnet to help keep the magnetic domains aligned, therefore more energy is required to randomize the domains. You do know that you can 'magnetize' a screwdriver by holding a magnet close to it ? And after enough time, the screwdriver will retain the magnetism even with the magnet removed. What do you think the magnet is doing to all the ferrous magnetic domains in the screwdriver ?
Zet Posted January 25, 2015 Author Posted January 25, 2015 I doubt that. It is. Not another 'missing potential energy' question ?!?! Actually, the problem is with too much potential energy found. The two systems are different. It takes a certain amount of energy to 'randomize' all the tiny magnetic domains in the single magnet. If a second magnet is present, its field will act on the first magnet to help keep the magnetic domains aligned, therefore more energy is required to randomize the domains. Yes. I realize my first post in this thread is a long one. But there are three cases. The problem I'm having involves the third case. You and I agree about the first two cases.
Zet Posted January 26, 2015 Author Posted January 26, 2015 I made two bad typos in my original post. In a footnote I switched “increase” and “decrease” (although this doesn’t affect the overall statement of the issue) and in another sentence I left out the word “to” (the absence of which makes the sentence nonsensical). I should have written ... “(If the potential energy between them due to mutual attraction is positive then there needs to be an additional increase decrease in thermal energy, if the potential energy between them due to mutual attraction is negative then there needs to be an additional decrease increase in thermal energy, and if the amount of potential energy between them is 0 then there needs to be no change in the amount of thermal energy, to then offset the change (or no change) in the potential energy between them due to the loss of mutual attraction.)” And ... “When one of the magnets is demagnetized it is instantly cut off from the shared magnetic field and so whether the other magnet is demagnetized at the same time or whether it remains magnetized is immaterial to the demagnetized magnet (or magnets).” Apologies (... if anyone made it through my rather lengthy post).
John Cuthber Posted January 26, 2015 Posted January 26, 2015 It is. Guess again, unless you think that things spontaneously roll up hills. Since you have the direction of the energy change wrong it's no wonder you think the energy changes don't add up. 1
Zet Posted January 26, 2015 Author Posted January 26, 2015 John Cuthber: The issue in my (rather lengthy) first post in this thread is too much potential energy found in the end. Whether or not the demagnetized state is a higher or lower or equal energy state to the magnetized state is tangential to the issue presented. But ... thank you for challenging me on this. I want to make sure everything is accurate (even if it is not essential to the core of the issue). I understand you disagree with me. Do you also disagree with imatfaal? “The parallel spin state of a ferromagnet is a lower energy configuration than the jumble of a non-magnet - it takes energy to make it lose its array of similar magnetic domains.” http://www.scienceforums.net/topic/87342-where-does-the-potential-energy-of-a-field-reside/?p=847543 And do you also disagree with MigL? “It takes a certain amount of energy to 'randomize' all the tiny magnetic domains in the single magnet.” http://www.scienceforums.net/topic/87489-a-magnet-is-demagnetized/?p=849512 If it takes energy to change a body from one state to another then that state it is changed into is the higher energy state. Please let me know if you still disagree with me, while not with your two colleagues, if you can find a way to distinguish my statement from theirs. ?
John Cuthber Posted January 26, 2015 Posted January 26, 2015 Zet, This " The demagnetized state is a higher energy state than the magnetized state." is just wrong. Yes I disagree with them. Domains form spontaneously, but bar magnets don't There's also an "activation"energy associated with getting the domains to randomise. That's why it happens faster for hotter magnets. If you want to generate a magnetic field, you need to supply energy. Destroying the field releases energy, sometimes violently. http://en.wikipedia.org/wiki/Superconducting_magnet#Magnet_quench
Zet Posted January 26, 2015 Author Posted January 26, 2015 Thank you for the link, John Cuthber. Again, whether the magnetized state is a lower, higher or equal energy state to the demagnetized state is not what leads to the issue presented in the first post in this thread. I included it as a matter of housekeeping and in an attempt to include all of the changes. If magnetization is a higher energy state or an equal energy state to demagnetization, in the end, there is still too much potential energy found. However, having said that, the link you presented leading to “Magnet quench” occurs with superconducting electromagnets. And I’m sure there are both similarities and differences between an electromagnetic and a ferromagnet. In the article you linked to it reads “This [Magnetic quench] can occur because the field inside the magnet is too large, the rate of change of field is too large (causing eddy currents and resultant heating in the copper support matrix), or a combination of the two.” If you are suggesting that the same thing occurs with ferromagnets, I am at a lost for how “the field inside” a ferromagnet can be too large? Are you saying when a ferromagnetic is in its magnetized state that the field that comes from this can be “too large” for the magnet itself and thus can cause the ferromagnetic to undergo “magnetic quench” due to its own field being too strong? And are you saying that as a ferromagnetic is magnetized or demagnetized, and so there is a “rate of change” in the field, that something analogous to “heating the copper support matrix” occurs even though there is no “copper support matrix” with the ferromagnetic? And, finally, if there is a concentrated amount thermal energy around a ferromagnet putting it above its Curie temperature and then this thermal energy disperses and the ferromagnetic is cooled to below its Curie temperature and so then spontaneously magnetizes, are you saying that the amount of thermal energy within the system decreases? (This must be the case, if you are right and the magnetized state is a higher energy state than the demagnetized state, for energy to be conserved.) Does the spontaneous magnetization of a ferromagnetic also absorb heat? Again, whether or not the demagnetized state or the magnetized state is the greater, lesser, or equal state(s), is beyond the issue presented here. However, it is important to get all of the details (even the tangential details) right. So ... thank you for this discussion. Do you have any links (other than ones involving electromagnets) that support your position? Again, I am open to being corrected. ?
MigL Posted January 27, 2015 Posted January 27, 2015 Sorry, I see we must use our words carefully. Yes John is right, the demagnetized state is not a higher energy state than the magnetized state. But yes, energy must be supplied to 'quickly' randomize the domains. Natural demagnetization occurs slowly ( unless you're talking about the collapsing field of an electromagnet ) and the energy is 'lost' since it becomes entropic. There are only two ways to arrange the magnetic domains in a bar magnet while the domains of a nonmagnetic piece of iron can be arranged myriad ways. I.e. higher entropy.
Zet Posted January 27, 2015 Author Posted January 27, 2015 (edited) What I should have written in my first post is this: “There is a decrease in chemical potential energy. There is an increase in thermal energy. There is an increase in energy in the form of demagnetization. There is a change in the amount of energy in the form of demagnetization versus magnetization. And there is a change in the amount of potential energy due to mutual attraction between the two magnets.” This way I could have avoided the discussion of whether magnetization or demagnetization is the higher energy state, while still noting the energy change, and moved on to the issue I’m having with too much potential energy found. ----- However, having said that, it’s interesting (in a sort of meta-analysis way) that if you type in “is magnetization the higher energy state” or “is demagnetization the higher energy state” into Google you don’t get, I find, a simple clear answer. (And, sadly, if you type in the latter now this forum discussion now is the first thing to come up.) Here is a link and a drawing that I came across that may be helpful to this discussion: http://www.irm.umn.edu/hg2m/hg2m_d/hg2m_d.html (A similar description can be found in Wikipedia: https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&uact=8&sqi=2&ved=0CCQQygQwAA&url=http%3A%2F%2Fen.wikipedia.org%2Fwiki%2FMagnetic_domain%23.22Magnetized.22_states&ei=CtLHVLywPIHsgwST8oKwBw&usg=AFQjCNF9pBJb-Cn32--VcvgwwFmMEzlwhg&sig2=ONWT3-k9bSJNrpwUATdS5Q&bvm=bv.84349003,d.aWw) The professor is positing that the preferred energy state for a ferromagnet is multi-domain rather than single domain (and the more domains the better). And the combined fields from the multi-domains tend to cancel one another out at a distance, and so when there are the maximum number of multi-domains possible the ferromagnet does not have much of an external magnetic field. To quote Wikipedia, the magnet has been “unmangetized.” This is different, however, from what I believe we have been discussing here. Randomization of the magnetic dipoles (which is what occurs upon reaching and exceeding a ferromagnet’s Curie temperature) is not the same as multi-domain magnetic alignment of the magnetic dipoles. John Cuthber, you wrote: “Domains form spontaneously, but bar magnets don't” And so, perhaps, you believe that multi-domain magnetic alignment of the magnetic dipoles is the lower energy state and a single domain bar ferromagnet is the higher energy state. ? (I do.) But this is not an issue here. Here we have a single domain bar ferromagnet that then becomes demagnetized (it becomes randomly magnetically aligned not turned into multiple lines of alignment). And if more and more domains of alignment is the lower and lower energy state, then it stands to reason that going in the opposite direction from a single domain alignment to randomization (no alignments) should be then the higher energy state. (Otherwise, when you have a single domain bar ferromagnet there would be the two competing tendencies to, one, increase the number of aligned domains and, two, move towards less alignment and to randomization. And this is a logical impossibility.) But ... again, again, again ... whether or not the magnetized state or the demagnetized state is higher, lower, or equal to one another is beyond the scope of the original issue in this thread. If the demagnetized state is the higher energy state, then there must be a decrease in thermal energy upon demagnetization. If the magnetized state is the higher energy state, then there must be an increase in thermal energy upon demagnetization. And if they are equal energy states, then there must be no change in thermal energy due to this upon demagnetization. But then, regardless of which of the three above conservation of energy options is true, the logic in the first post in this thread still leads to too much potential energy found. This side discussion has been interesting. And, thank you all, I am learning (whether you believe I am or not). Edited January 27, 2015 by Zet
CasualKilla Posted March 24, 2015 Posted March 24, 2015 Guys come-on really . "magnetic potential energy" = "change in potential energy between the two magnets due to their loss of mutual attraction". Does anyone disagree with that definition? If not can we move on and answer this man's question? I agree that the question is magnetized or magnetized state higher energy is interesting and important, but it is not relevant to the question posed by the OP.
Mr. Astrophysicist Posted March 31, 2015 Posted March 31, 2015 Metallic objects are magnetic, but not all of them are. The reason is because the electrons are lined up in such a manner that it has a magnetic field, as described in Maxwell's equations.
swansont Posted March 31, 2015 Posted March 31, 2015 Metallic objects are magnetic, but not all of them are. The reason is because the electrons are lined up in such a manner that it has a magnetic field, as described in Maxwell's equations. There are three forms of magnetism, and everything displays one form or another (you can magnetically levitate a frog), so "magnetic" isn't particularly descriptive. Often it's meant to mean ferromagnetic, and most metal aren't (at room temperature).
John Cuthber Posted March 31, 2015 Posted March 31, 2015 I'm fairly sure that paramagnetism is a quantum effect and that Maxwell's equations are classical so you can't explain magnetism with Maxwell's equations.
MigL Posted April 1, 2015 Posted April 1, 2015 First you're dropping cats upside down. Now you're levitating frogs magnetically. Is there no end to your cruelty swansont ? What's next ? Shooting chickens around the LHC ? 2
imatfaal Posted April 1, 2015 Posted April 1, 2015 First you're dropping cats upside down. Now you're levitating frogs magnetically. Is there no end to your cruelty swansont ? What's next ? Shooting chickens around the LHC ? You should see his herd of spherical cows...
John Cuthber Posted April 1, 2015 Posted April 1, 2015 You should see his herd of spherical cows... Not to mention his swarm of grounded bumble bees.
swansont Posted April 1, 2015 Posted April 1, 2015 First you're dropping cats upside down. Now you're levitating frogs magnetically. Is there no end to your cruelty swansont ? What's next ? Shooting chickens around the LHC ? When I taught, there was always an abundance of blue chalk, so most of my kinematics projectiles were smurfs. Anyway
Zet Posted April 7, 2015 Author Posted April 7, 2015 . The demagnetized state is the higher energy state and magnetized state is the lower energy state. “... this torque tends to line up the magnetic moment with the magnetic field B, so this represents its lowest energy configuration” http://hyperphysics.phy-astr.gsu.edu/hbase/magnetic/magmom.html “... the energy is lowest when the magnetic moment is aligned with the magnetic field.” http://hyperphysics.phy-astr.gsu.edu/hbase/magnetic/magpot.html “This reduces the electrostatic energy of the electrons when their spins are parallel compared to their energy when the spins are anti-parallel, so the parallel-spin state is more stable.” http://en.wikipedia.org/wiki/Ferromagnetism “This "spin flip" places some of the spins in their higher energy state. If the radio frequency signal is then switched off, the relaxation of the spins back to the lower state ...” http://hyperphysics.phy-astr.gsu.edu/hbase/nuclear/nmr.html But this is irrelevant to the issue presented here. .
Zet Posted April 10, 2015 Author Posted April 10, 2015 . (Please note: I posted this question as its own new separate thread ... I thought it was distinct enough to warrant a new conversation ... I was wrong ... I misjudged the parameters of the rules of this forum ... I apologize ... I hope that I am now able/allowed to post it here, in this thread, even though I've already posted it in its own separate (and locked) thread ... thank you ... and, again, I apologize for my misjudgment.) There is an even simpler form of this question; with demagnetized and moving magnets. There are two closed systems. In terms of energy each system is identical. In each system, there are two magnetically aligned ferromagnets. One is fixed in place, and the other one is in motion moving towards the fixed one due to their mutual attraction. In each system, there is a chemical heat pack. If the chemicals are exposed to one another thermal energy will be generated. The temperature in the vicinity of the heat pack after the chemical exposure will be greater than the Curie temperature of the ferromagnets. (And after that, the thermal energy will then dissipate throughout the rest of the system.) The chemical heat pack is placed at one location in the one system and in the other system the chemical heat pack is placed near the fixed magnet. In both systems, when the two magnets in the two sets are the same distance apart, and when the moving magnet is near the heat pack in the one system, the chemicals are exposed to one another. The temperature in the vicinity of heat pack increases to more than the Curie temperature of the ferromagnets. One magnet is each system becomes demagnetized. (The magnets are close enough to one another to be attracted to one another (even if only slightly) while far enough away from one another so that the magnetic field of the other non-demagnetized magnet is not strong enough to keep the heated magnet externally significantly magnetically aligned.) There is a of loss mutual attraction between the two magnets. The remaining amount of potential energy between them as they have gotten closer is now gone. The demagnetized magnet is immediately cut off from the mutual attraction. But the lack of mutual attraction takes some time to make its way across the distance to the still magnetized magnet. It remains attracted to the other magnet for a while longer. The means in the case where it is the moving magnet that is demagnetized the moving demagnetized magnet immediately ceases to continue to accelerate, while in the other case where it is the fixed magnet that is demagnetized the moving still magnetized magnet continues to accelerate for a little while longer. In the end, in both systems, the thermal energy will dissipate throughout the entire closed system and both magnets within it will be raised above their Curie temperatures. The two moving magnets, in the two different systems, will continue to move. In the end the two systems are identical in many respects. There is the same decrease in chemical potential energy. There is the same increase in energy in the form of the magnets’ demagnetizations. And there is an increase in thermal energy. In the one system, there is, however, more kinetic energy in the end than in the other. And since both systems started out identical energy-wise they must end up with identical total amounts of energy, according to the logic of the Law of Conservation of Energy. And so, in the end, in the case with more kinetic energy there must be less of another form of energy, and in the other case with less kinetic energy there must be more of this other form of energy. What is it? Or, is there a flaw in the logic of the “Laws of Physics” in this situation? ? --- Endnotes. 1: The demagnetized state is the higher energy state and the magnetized state is the lower energy state (but this is irrelevant to the issue presented here). 2: It is a loss in thermal energy that demagnetizes each magnet and thus raises each magnet’s energy state. 3: The only possibility I can see is, in the end, there must be less thermal energy in the system with more kinetic energy and more thermal energy in the system with less kinetic energy. This means it must take more energy to demagnetize the fixed magnet (a greater decrease in thermal energy) and where the moving magnet continues to accelerate, and less energy to demagnetize the moving magnet (a lesser decrease in thermal energy) and where the moving magnet immediately discontinues to accelerate. But if anything it seems as if the exact opposite should be true. As the moving magnet moves towards the fixed magnet the strength of the moving magnet’s field moves too. Whereas the moving magnet moves across positions where the strength of the fixed magnet is already there. And so, at the time of demagnetization of each different magnet in the two cases, when the distance between the two magnets in both sets is identical, the strength of the magnetic field from the fixed magnet on the moving magnet could be stronger than the strength of the magnetic field from the moving magnet on the fixed magnet. And it stands to reason that the stronger the external magnetic field is on the demagnetizing magnet the more energy it would take to demagnetize it. But this leads to the exact opposite conclusion needed. This leads to that it would then take more energy to demagnetize the moving magnet, which is also the case where there is less kinetic energy in the end, and so there would both be less kinetic energy and less thermal energy than in the other case. This only exacerbates the problem. 4: There is also an empirical answer, if one has the skills and resources to find it. However, regardless of what the empirical answer turns out to be, the logic must work first or no matter what the empirical answer turns up to be it will not be one where energy is conserved. 5: If the loss of mutual attraction does not take time to cross the distance between the two magnets and to the still magnetized magnet, but is rather instantaneous, then this would lead to all sorts of Special Theory of Relativity paradoxes. 6: The “demagnetized” magnet will never fully become magnetically disaligned. And so, the moving magnets will continue to accelerate after the “demagnetization” of itself or the other magnet. However the residual magnetic alignment and the remaining continued acceleration are so minuscule so as to be reasonably ignored. 7: In reality, no mutually attracted body is “fixed in place.” They both are moving towards one another. But if the “fixed in place” magnets in the two systems above are connected to a massive body such as planet Earth, then the acceleration of the “fixed in place” magnet and the associated massive body is so miniscule so as to be reasonably ignored. There is an equal increase in momentum in opposite directions between the “moving” magnet and the “fixed in place” magnet and associated massive body (p = mv), but the increase in kinetic energy of the “fixed in place” magnet and associated massive body is miniscule compared to the increase in kinetic energy of the “moving” magnet and so can be reasonably ignored (ke = ½mv2). (However, whether it is the “moving” magnetic that continues to accelerate for a time while the other demagnetized body and associated massive body does not or whether it is the “fixed in place” magnet” and associated massive body continues to accelerate for a while while the other demagnetized body does not, either way, there is also a possible violation of the Law of Conservation of Momentum.) 8: The fact that one magnet is in motion relative to the chemical heat pack and the other magnet is not is irrelevant unlike other aspects of magnetic movement, such as Lenz’ Law, where the nature of any relative motion is a factor. 9: When two bodies are in two different motions, such as the faster moving magnet in the one system versus the slower moving magnet in the other system, they are in two different frames. And the total amount of energy can vary between frames. However, the two frames in comparison here are the two “fixed in place” frames and not the frames from the perspective of the “moving” bodies at rest, and so the total amount of energies between the two systems considered are in the same frame and so must end up with the same total amounts of energy in each for the logic of the Law of Conservation of Energy to not be violated. .
Zet Posted April 12, 2015 Author Posted April 12, 2015 . Hello. If anyone has the time, could you please show me why the question in post #21 does not lead to a violation of the Law of Conservation of Energy? Thank you. - Zet I’m always willing to learn. I worked hard on the question. .
Zet Posted April 14, 2015 Author Posted April 14, 2015 . Silence, generally, means consent. “Silence implies consent” http://c2.com/cgi/wiki?SilenceImpliesConsent “he who is silent is taken to agree” http://en.wikipedia.org/wiki/Silence_procedure “Silence means consent” https://www.englishclub.com/ref/esl/Sayings/S/Silence_means_consent_925.htm “Silence gives consent” http://idioms.thefreedictionary.com/Silence+gives+consent Can I take the collective silence of the members of Science Forums to mean that I found a violation of the Law of Conservation of Energy in post #21? (I realize my original post in this thread is very long, but I worked hard to present the issue in a much shorter form in post #21 (especially if you just look at the question and ignore the endnotes).) Or, is my question in post #21 so embarrassingly stupid that it’s not worth anyone’s time to comment? Or, something else? ? .
John Cuthber Posted April 14, 2015 Posted April 14, 2015 For a start, please stop making your posts difficult to read.
Zet Posted April 14, 2015 Author Posted April 14, 2015 For a start, please stop making your posts difficult to read. . I guess I would characterize your response as “reductio ad absurdum with font formatting.” That’s it? Am I to understand that the problem with my question in post #21 is not logical or factual but rather “an improper use of fonts”? The endnotes in post #21 are superfluous to the question and so are accordingly diminished in size. They are merely there in anticipation of the kinds of tangential issues that may arise when addressing the question. The actual question itself should be easily readable. I realize the original post in this thread is very long and probably no one (or hardly anyone) read it. But the reformulated question in post #21 (sans endnotes) only takes a couple of minutes to read. Does anyone have anything to say about the substance of the issue raised in post #21? (BTW: I can repost the text of post #21 in a large plain format such as 18 point Courier New. Would you like me to do so?) .
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