exchemist
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Posts posted by exchemist
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1 hour ago, ImplicitDemands said:
Thank you for repeating that.
Proteins are made out atoms which have electrons. So at the very most basic level what is happening is literally ionization from light in the dna composing the retina. Yes when you get to the cellular level things like photosynthesis seem more complex but it's all just light and electricity interacting with each other just like the computer.
No, this is wrong. You need to understand the difference between excitation and ionisation. Photons are often absorbed without having enough energy to eject an electron. They just move it to a higher, but still bound, energy state. This creates an excited state of the atom or molecule that has absorbed the photon. The whole of spectroscopy involves processes of this kind.
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7 minutes ago, TheVat said:
Is there a load on the circuit, and is it a dumb load (lightbulb, e.g.) or a smart load (electronics)? When your current passes the load in a series circuit, there is a voltage drop from hot to neutral (the return leg). Even without a service load, more than 50 feet of cable (like 12 or 14 AWG in a house) will cause a voltage drop. Good old R. (well, Z actually, in an AC circuit)
The voltage drop across the load is proportional to the power available to be converted in that load to some other useful form of energy.
In an AC circuit we speak of impedance. Several factors at work there.
Besides resistance, AC voltages have a second opposition to current flow called reactance. The sum of resistance and reactance is the impedance. (Z) Z will depend on the frequency of the AC and the magnetic permeability of electrical conductors and electrically isolated load elements.
I wonder, though, whether this question may be about something else, viz. the "elasticity" of the current-carrying electrons in the circuit. For instance is the voltage is at its maximum value at one end, what will be the phase of the voltage 10 metres along the wire. Will that also be at the max, or is there a phase lag due to the compressibility of the current carriers?
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6 hours ago, ImplicitDemands said:
An LED is basically the reverse of photovoltaics, i.e. electroluminescence.
As for it's own magnetic moment, whatever the culprit is that doesn't change the fact that magnetization is the point where the two opposing orbitals cross paths as those sides of the atom are adjacent. When I said spin I meant orbital magnetization. As in the port where the fiber optic cable connects to battery a, photoionization occurs and the conductor connecting battery a to battery b adopts one atomic orbital which attracts one end of the cylinder which has a magnet, then the orbitals reverse throughout the conductor as the positive ionized battery a takes back the additional electrons from the negatively ionized batter b, attracting the other end of the cylinder which has an anti-magnet. Your retina are like little photovoltaic batteries, their cells can experience photoinization which is not unlike the process of photosynthesis or why ionized gas in hydrothermal vents are the culprit for the creation of chemical bonds leading to the carbon based dna in our cells. If you have LEDs that are small enough, I'd wage the easiest was to program them to light up in just the right combination to produce a picture through our retina I'd wager the easiest way to program a touch screen interface is what I described here but I can use math to figure out exactly how that interface needs to be set up.
Hard to know where to start with this gibberish. Almost everything you say is wrong, almost as if intentionally so.
Just to take one point, there is no photoionisation in the retina of the eye. Photons are absorbed by proteins called opsins, which thereby enter an excited state and change from one isomer to another (cis ->trans). The isomerised version then undergoes a chemical reaction with other molecules to start a cascade of biochemistry, resulting in a nerve signal. This is not photoionisation.
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36 minutes ago, John Cuthber said:
Reflection from the retina is what causes red eye in flash pictures.
https://en.wikipedia.org/wiki/Red-eye_effect
And you really need to look up what "intromission" means.There is apparently a meaning relating to an Ancient Greek theory of sight, in addition to the more, er, Sid James sense of the word.......
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16 hours ago, Mordred said:
The better question is what gives rise to the B field. The E field current generates the B field. With permanent magnets the E field current is generated due to the electron charge alignments as per ferromagnetism so there is always an E field current allowing the B field
If you take a rotor for example and law it on its side so the opening is facing you the E field current will be through the center of the rotor heading either towards you or away from you depending on the magnetic pole alignment. What allows the rotor to turn depends on varying the E currents with the different poles of the rotor. Typically 3 poles for 3 phase motors. The phase shifts provides the differences in current in each pole. It is still the E field performing the work.
For DC motors it's much the same you send pulses at selected poles to generate the field variations to induce rotation. The number of poles is equal to the number of signal wires the device has and you send pulse patterns to the DC stepper motor.
OK, I'm trying to follow this in the context of a permanent magnet. I'm not finding the motor analogy very helpful (sorry, my background is chemistry rather than engineering). I'm aware that ferromagnetism arises due to aligned, unpaired electron intrinsic "spin" and orbital angular momentum. So I presume the "current" you refer to in this case would comprise the "spinning" (not really but let's call it that) and orbital motion of the electrons. Is that right? But it seems to me this aligned angular momentum does not lead to an overall E field external to a bar magnet, which can interact with a nail some distance away. Or does it?
If, as you say, the energy in the magnet that changes, when the nail is brought close to it, comes from the E field, what change do we get at the atomic level? Are we saying the quantum states of the unpaired electrons drop slightly in electrostatic energy, e.g. their mean distance from the nucleus reduces fractionally, or something like that?
21 minutes ago, Prajna said:Splendid. Now all I need is for someone like @exchemist to translate this into simple terms that I can comprehend. I am still studying the wiki, btw, in the hope that I can get to a broad-brush understanding of how magnetism works.
As you will see, I am trying to get a physics tutorial on this from @Mordred, who is I gather a professional physicist (respect).
It looks to me so far (i.e. pending what I may be about to learn) that I may have been a bit too cavalier in strict physics terms in claiming the work done by, and on, your magnets comes from what I have been calling "the magnetic field". We are now into a discussion of the E field and the B field and where exactly the extra energy due to magnetisation resides in a permanent magnet.
I think though that, in terms intelligible to a non-physicist, we can still say it is the extra energy in the fields due to their magnetised condition that rises and falls as work is done.
But let's see what brother Mordred comes back with. I just hope I have enough grey cells left, at approaching 70, to take in a change in my mental picture of how this all works. 😀
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24 minutes ago, Mordred said:
The E field not the B field. Doesn't matter if it's a permanent magnet or an electromagnet it's still the same.
To help understand the permanent magnet if you look at inductance it does have both the E and B fields .
The reason why the B field has less energy and doesn't do the work involves how the field diverges as opposed to the E field coupled with the Lorentz force law via the right hand rule. That directly relates to Swnsonts previous statement with regards to the cross product for the B field as opposed to the inner product of the E field
OK, but what gives rise to the E field in this case and what form does it take?
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1 hour ago, swansont said:
Depends on the configuration, but one question to ask is how the nail and magnet got close enough for this to happen. Permanent magnets don’t turn on, and these objects don’t magically appear close enough to each other for this to happen.
I don’t think that matters. But let’s say it has been brought up from infinity (a concept physicists seem to like), held in place on the table and then released. Work is done against friction as the nail moves towards the magnet. What provides the energy?
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44 minutes ago, swansont said:
The energy is insufficient to do that, and that’s not the source of the work - the magnetic field does not get depleted by attracting something. As I’ve pointed out before, something is holding, pushing or pulling the magnet. The magnet is like a chain used to lift something; it exerts a force, but that’s not where the energy comes from.
If a nail is attracted towards a permanent magnet, doing work against friction, where does the energy come from?
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22 hours ago, swansont said:
You should open up a thread to ask questions. People could answer, or point you toward sources that would explain it. Of course, you could also pick up a physics textbook. You’d eventually find that a changing B field creates an electric field, and that can do work, and also that the energy in the magnetic field is fairly small, and is not the source of the energy.
I’m explaining that the work in your device comes from whatever turns the rotor, not the magnets (which are just a substitute for a mechanical coupling, which would also not be doing work). You even acknowledge this, when you agreed that this device would not run on its own. Someone has to turn the crank. That’s where the energy comes from.
Right. But, to be clear, there is energy in the magnetic fields, which can be made to do mechanical work, for instance in my example of the nail being drawn towards a permanent magnet, against the force of friction with a table top.
My attempt at analysing the operating cycle of this reciprocating machine was to show how energy is alternately drawn from and returned to the fields generated by the pair of opposed magnets, so the net effect, over one operating cycle, is as you say, no net work done by the magnets and a mere transfer of input mechanical work to output mechanical work.
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33 minutes ago, Prajna said:
Sorry to have been quiet, I've been redoing my animation to better represent movement (or approximated movement) in the device. @exchemist, I do hope to ask for some more detail regarding your analysis, particularly regarding what you consider as Stroke 4 in your analogy. @sethoflagos, I am also interested to explore hysteresis further to estimate what part it plays in the dynamics of the device. @swansont, thanks for the further response. It seems to me that you make bare assertions, such as, "Magnets don't do work" and the above, "The energy for doing stuff with magnets is not contained in the magnetic field." Now, most likely you are right and it just remains for us to research deeply enough to understand your assertions but it would be much more helpful if you would offer some explanations to go along with your assertions. Thank you.
Yes, it would be good to understand exactly what @swansont means. I suspect it may be the simple point that a magnetic grab, once it is clamped onto an object, does no work when the crane lifts said object.
However, when a permanent magnet on a table top draws a nail towards it, against the force of friction, work is clearly done. That work, it seems to me, must be drawn from stored energy in the magnetic field.
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21 minutes ago, swansont said:
Just FYI, the energy density of the earth’s magnetic field is about a millijoule per cubic meter. Scale up as necessary for a stronger magnet. The energy for doing stuff with magnets is not contained in the magnetic field.
That's interesting. I had always understood that magnetic fields have energy, as for example in the stored energy in an energised electromagnet. If they do not, where does the energy come from when an object moves towards another under the influence of magnetic attraction? And you yourself say a magnetic field has an energy density.
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2 hours ago, Sora Tōgo said:
Hello, world. I’m eager to share the motivations behind my work with you all.
As Michio Kaku points out, we are a level 0 civilization—it’s time for us to advance. I deeply appreciate the monumental efforts and contributions of our scientific pioneers and current researchers. Yet, considering it has been over three centuries since Newton and a century since Einstein, we must ask ourselves: What’s next?
Let’s unite our strengths, incorporating AI and interdisciplinary collaboration to transcend traditional boundaries. It’s time to set aside personal biases and collectively push the frontiers of science. Together, we can explore the cosmos and develop new energy sources—not just for us, but for future generations.
Sora Tōgo
Information is related to entropy, but is not energy and can’t be “turned into” it.
You don’t know what you are talking about.
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2 hours ago, md65536 said:
I've seen this posted on this site many times over the years and I think it's wrong but never saw a correction or explanation. It's repeated often in posts labelled "expert" but I don't understand what it means. As a Lorentz transformation doesn't a boost imply constant velocity? How can a measure of velocity be called an acceleration? How is a measure of velocity a type of Lorentz transformation?
Is there some sensible meaning to what I quoted that I'm just not comprehending?
Well, I had no idea rapidity had a technical meaning in the context of relativity, so I've learned something already! But having looked it up here: https://en.wikipedia.org/wiki/Rapidity, I'm definitely going to leave it to you chaps in long trousers.......
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1 hour ago, CodeBreaker said:
This is your science you hypocrite?
"As soon as you abandon scientific rigor, you’re no longer a mathematician. You’re a numerologist." Meaning what genius? Do you know what science is? Look it up, it isn't "my huffing and puffing and telling someone they aren't being scientific and my personal feelings." Your reply isn't scientific, and you show massive ignorance and superstitious stupidity by saying "numerology" as if means "opposite of math". It means study of numbers you numbskull ignoramus. Duh can't you see the word components you giant moron? Science isn't merely "math" and science has nothing to do with your rigor mortis brain, there is no "science is rigorous" in any dictionary you pretentious oaf. Science is not just basic addition and subtraction that you half learned in your woke rainbow school in downtown Chicago it is also theology, gematria, linguistics, textual criticism (as in the study of ancient texts), cryptology, psychology, statistics none of which any of you seem to be adept in, unlike me, with the exception of statistics, but I do use statistical analysis. It's also archeology, which no doubt you are all repelled by who hate the Bible being that you hate your Creator. Something the load of you babblers don't know due your complacency and hate for God is that the Bible is filled with math codes, that besides symbology, metaphors, riddles, musical annotations, acrostics, prophecies everywhere, codes all over the text, and even encrypted codes. Unlike most of you empty babblers babbling in ignorance I know this as I bothered to study the research, it's all over the net including YouTube, besides that I have code scanning software and have been using it for years. Another thing most of you don't seem to remember is to apply scientific analysis to the supernatural not simply material. For exanple if God hates everyone as Psalm 5:5 says, due to their arrogance and hatred for him, well then as Jesus said count on being confused and blinded, deluded with Satan's hell, God's weapon against mockers, scoffers and arrogant hatemongers. And you love God and are humble and asked him for extreme wisdom (for HIS GLORY not yours) repeatedly, it is reasonable he would comply. So then don't expect to know anything but what is shallow with regards to God's word. Why would he share his secrets with those he sees as imbecilic mocking goblins and next to no morals, morals are required for correct science, did you forget? Yep. Stop with narcissistic gaslighting and feelings babble. You are like the Pharisees Jesus said he was thankful God his his secrets from. Repent and turn to Christ before the Antichrist subdues you and gets your spiritually dead selves to take his mark. Do you know what his name is? I do, your harbinger of doom: he will strike your heel, but you will strike his head God said of his chosen. And when Antichrist comes back to life will you then believe in the supernatural? Will you believe if dead man comes back as a spirit to tell you there is life after death? How many videos of people using ouija boards or going into haunted houses or spots or talking to demons they think are dead people using stupid electronic contraptions do you need to see? You have no brain to "scientifically analyze" what you see and hear, you are that blind and stubborn? So if a rock out of no where hits your eye in a haunted house is it science to think, "oh rocks just fly all the time, oh it must have been a midget hiding in the dark or bats that throw rocks or my friend conspired to blind me". That's your science, conspiracies everywhere. Narcissists are paranoid, big surprise.
This abusive approach does not seem likely to make a person “repent and turn to Christ”. Surely it is more likely to confirm them in their low opinion of religions and religious people generally, isn’t it?
From a stylistic point of view, some paragraphs would help, too😉
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17 minutes ago, Michael McMahon said:
One reason sweets can be addictive is that healthy food is almost unlimited such that healthier people would still be outcompeted by even healthier people. I’ve never ate a whole raw lemon and lime until now where I had plenty of lemon and lime juices in the past. So many sugary sweets during childhood are almost mere preparation for how extreme it could be to eat lemon and lime slices. I ate the lemon yoghurt afterwards as a recovery warm-down! I put a handful of raw popcorn in my mouth on a drive to the beach and it took the full 30-minute length of the journey for the popcorn to melt in my mouth before it became chewable and ingested. Yet in spite of the blandness the raw popcorn was as great as chewing gum in distracting you from overeating other foods.
Look, from all your posts it is plain you have a really unhealthy relationship with food. That previous picture you posted on the 14th of March was positively disgusting. And now you ballock on about eating whole lemons and limes on their own, which is nuts and certainly nothing like part of any reasonable, balanced diet. The acid alone will screw with your stomach.
I don't know what you are doing on this forum. You've been given all the advice you need long since. Go and talk to a dietician and act on what they say. Stop trying these random daft things and then coming here to obsess about it. I'm sorry, but I've really had enough of this crap.
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17 minutes ago, TheVat said:
Thread seems real similar to another thread started Sunday by same poster, with some of the same questions raised. Just curious why two threads needed.
Suspect the biological question was to open the door to these dubious social ideas now being advanced. We shall see.
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43 minutes ago, JohnDBarrow said:
I'm not here to argue anything. I came to ask questions. I want to know what YOU think the answers might be. If you don't honestly know the answers then please say you don't know. I'm only seeking opinions. I focus on the human species because there is a cultural aspect of the sexes not possessed by other animals. Female dogs don't wear lipstick.
But you are not only asking questions. You are making contentious assertions - or at least advancing contentious opinions - too.
You say it seems that the male of the human species is becoming less relevant. You cannot expect us all to go along with this without challenging it, because it is patently ridiculous. The human male has dominated human societies for millennia and a quick glance at the sex of those occupying positions of power and influence in modern societies will show you they are still predominantly male.
We can't just answer your questions, if your questions start from a false premise. Surely you must understand that?
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1 minute ago, Prajna said:
I did add a rather conspicuous wink but thanks for the clarification.
OK.
36 minutes ago, sethoflagos said:You're not answering the question I asked.
When there is a tab directly between the magnets, are the magnets at minimum separation, maximum separation, or somewhere in between.
Just to be absolutely clear on where you want to push and when you want to pull. It makes a difference. Rather like the ignition timing on a combustion engine.
As I understand it, the idea is inserting the tab, or finger, causes the magnets to be attracted to it, instead of repelled from one another as they are in the previous phase of the motion.
If we describe the operation in terms of an engine cycle, there are 4 phases:-
1) magnets close together no tab inserted, high energy of the field
2) magnets have moved apart due to mutual repulsion, reduction in field energy. Work imparted to output shaft
3) tab or finger inserted into the gap, causing magnets to be now attracted towards it, with further lowering of field energy. More work output to the output shaft (and some work output to the input shaft as well, due to the attraction)
4) tab removed from the gap between the magnets, which are now close together. This replaces the force of attraction to the tab or finger by mutual repulsion of the magnets, which are now at close separation, i.e. back to (1). It is this step that requires the substantial work input which returns the stored energy in the field to its stating value. Failure to realise the work need to do this is what can lead the incautious designer to think he has an over-unity machine, as the other steps all involve extracting work from the magnetic field.
At least, that is my energy-based analysis of this machine.
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1 hour ago, Prajna said:
In the current design the tabs or fingers are arranged every 20 degrees around the rotor. There are nine tabs and the rotor axle is co-planar with the centre line of the magnets, so when there is a tab central to the gap between the magnets on one side there is a space on the opposite side. The magnets are 10mm x 2mm neodymium (N52?) and the tabs centres are at approximately a 35mm radius. The 'bulb' on the tabs that lies between the magnets is 5mm radius to match the area of the magnets. This may be more or less optimal as far as effectiveness in switching the flux and suffering eddy current drag, I don't know yet.
This is somewhat arbitrary and is just my first best guess of what might work.
I wish you guys would stop with the perpetual motion slur, I'm rather hoping for over unity!
Over unity is the same thing as what is traditionally known as a “perpetual motion machine of the first kind”, i.e. one that claims to break the 1st law of thermodynamics. So it’s not a slur.
There have also been ideas for perpetual motion machines of the 2nd kind, which claim to break the 2nd law of TD instead.
As I have mentioned, it can be good sport to spot the flaw in the logic of the designer.
A rule of some patent offices, e.g. the US one, is patent applications for perpetual motion machines will only be accepted if accompanied by a working model. Which they never are, of course. So recognising perpetual motion machines is something patent office examiners (as Einstein once was,incidentally) and patent agents have to be able to do.
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28 minutes ago, Prajna said:
Sorry, I don't understand. Unless you mean it's a win that I'm belatedly reading about magnetism and you don't need to be involved in analysing the device.
By the way, I stumbled back on the article about monopoles, for anyone interested, it was in Popular Mechanics: https://www.popularmechanics.com/science/a60079037/magnetic-monopole-hematite/
Both: we’ve solved the conundrum presented by your machine, I’ve revised some magnetism I haven’t looked at since school, and you’ve become motivated to learn more about it. And for me, another perpetual motion machine bites the dust, which I can add to my tally.
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6 minutes ago, sethoflagos said:
Different words, same thing. It's the repulsion of like poles that causes the field rotation I took as a given for sake of brevity.
Oh I see.
20 minutes ago, Prajna said:It's not so unusual though for magnetic fields to be sharply bent, a keeper on a horseshoe magnet does this when placed across the poles, providing the shortest possible low reluctance path for the field and containing it, effectively neutralising the magnet.
By the way, I've just taken a look at the Ferromagnetism page on Wikipedia and am finding it very helpful in understanding magnetism. Soon I may be able to drop my naive model and speak intelligently about it.
Well that's a win, then!
It's been an interesting discussion.
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57 minutes ago, sethoflagos said:
Perhaps one way of looking at this contraption is to compare it with a Faraday disk (aka homopolar generator).
In the latter, both motion and induced current are in the plane of the disk with the magnetic field perpendicular. The OP is rotating this so that motion and magnetic field lines are in the disk plane therefore forcing induced current into the perpendicular. However, different portions of the disk will see different current polarities depending on whether they are moving towards or away from the magnetic poles. In particular, the portion of the disk passing directly between the poles will see a sharp switch in polarity and consequent current flow component appearing in the disk plane. This will in turn deflect the magnetic field lines somewhat out of the disk plane as if attracted by a temporary opposite pole.
I don't know whether it's a good picture, but in my mind's eye, I'm seeing this induced temporary pole falling into a potential well only to climb back out as it departs with no nett overall energy change in and of itself. However these circulating currents are a different matter as they will add a time lag to the ideal case making ascent harder than descent, acting as a brake in exchange for simply heating up the disk.
One important difference, though, is that in the OP's machine the poles of the two magnets are opposed so that they repel. The region in which the fingers on the input disc move is in principle an area in which the field lines will be squashed outwards in the plane of the fingers of the disc.
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1 hour ago, Prajna said:
This is exactly the conversation I hoped to have here, @exchemist. Yes, my preliminary experiments showed that with magnets in repulsion a steel sheet, in this case a steel rule, inserted into the gap caused the magnets to be attracted to the rule. My guess at what is happening there is (if you'll indulge my less-than-physically-exact language) the magnets in repulsion, because their competing fields offer a very high reluctance to the other's flux path, try to complete their circuit by adopting (and attracting) the steel rule, a much lower reluctance path, into their circuit. When the rule is removed the magnets again face an unacceptable high reluctance to their circuit and therefore attempt to mitigate it by moving apart.
OK, in that case, what I think you will find is it takes significant effort to pull the finger out of the gap, as the force of attraction is stronger once the magnets have moved inward, than the force that pulls it into the gap when you insert it. So you do net work on the system that way and this provides the energy that restores the stored energy in the fields to the status quo ante.
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2 hours ago, Lahearle said:
If I combine a compound which contain a ratio of 3/8 hydrogen/oxygen and heat it to 2600 F, according to PV = nRT
how much will the pressure increase when it reaches ignition temperature (1058 F), and how big do I need the container to avoid it exploding and spewing lava everywhere?
Yes I am noob so please talk stupid to me.
The compound has only hydrogen, carbon, oxygen and nitrogen.
Won't the answer depend on what the products of decomposition are going to be, as well as on the enthalpy change, which may heat the mixture further ? Both of these will depend on what your undisclosed compound is.
Also, why do you speak of "lava"? Lava is molten rock and rocks do not ignite, as a rule.
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What Would Be the Best and Most Efficient Way to Harvest the Energy of a Time Crystal?
in Modern and Theoretical Physics
Posted
No I don't think so. See the Wiki article: https://en.wikipedia.org/wiki/Time_crystal and especially this passage:
Time crystals do not violate the laws of thermodynamics: energy in the overall system is conserved, such a crystal does not spontaneously convert thermal energy into mechanical work, and it cannot serve as a perpetual store of work. But it may change perpetually in a fixed pattern in time for as long as the system can be maintained. They possess "motion without energy"[16]—their apparent motion does not represent conventional kinetic energy.[17]
I'll admit I know nothing about time crystals apart from what I have just quickly read, but it looks to me as if these things exhibit motion in their ground state. The definition of a ground state is it is the lowest energy state allowed for the system. From that it follows that energy cannot be extracted from the system (unless you break the system up, I guess, which would be a one-off exercise).
You have much the same thing with the zero point energy in a harmonic oscillator, or, to give a real example, in the vibrational ground state of a diatomic molecule. There is still residual motion, even at absolute zero (hence "zero point"), but none of it can be extracted as energy.