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He sought the advice of a mathematician who told him to work it out with a pencil.

Logically incorrect, even if the premise is true. Equivalent to “All dogs are mammals. I am a mammal, therefore I am a dog.”

Indeed. However, But when a magnet and something attracted by it move closer together, under the influence of the force of attraction between them, work is done. I am saying this comes from a reduction in the stored energy in the magnetic field.

Interesting about Chatham. I was surprised to see from the castle battlements an old (decommissioned?) submarine moored in the river, just downstream of the bridges carrying the railway and road. I might pop down the line from Victoria again some time and take a look. I think it's the next stop after Rochester. Back on the topic, yes there will be work done when the magnet and steel object move relative to one another under the influence of the force from the field. W= Fd, remember. But when the magnet is static, held to the beam by its magnetism, no work is being done. I think that is what @swansont meant by saying magnets don't do work, i.e. they don't do work when they are just sitting there, simply by virtue of being magnets, as it were! And there is no inexhaustible store of energy in a permanent magnet that you can draw on by incorporating it in a perpetual motion machine. There is finite (fairly small) energy imparted to it when it is magnetised and you can get a bit of that back, once only, by allowing an object to be drawn towards it. But if you separate them again as part of an operating cycle of some machine, you have to put the same energy back each time. So as I say, no free lunch.

Either of the two main smallpox vaccines can control it, so if it were perceived as important (eg by killing white people instead), it would be easy enough to deal with. We get the odd case here from time to time. Nature's way of telling us not to mess around with rope squirrels (suspected wild reservoir).

The musician finally gave up and began to erase all the lines of notes. His wife walked into the room and asked, "what is that smell?" "I'm decomposing," he replied.

This is a much more reasonable response, @exchemist, thank you. At least you understand what I'm talking about. So what is happening is that there is a movement of energy into and out of the magnetic field, much like storing energy in an inductor, I guess. That's what I was referring to as 'work', perhaps inaccurately. We might consider that the steel sheet is 'falling upwards' towards the magnet in its magnetic field, that when the steel sheet is on the table and the magnet is fixed 30mm above it there is a potential energy imposed by the magnetic field and when the steel is attracted up to the magnet then that magnetically induced potential energy is converted to kinetic energy until the steel sticks to the magnet. Now the magnetic potential energy has been converted to gravitational potential energy. Then if the magnet is an electromagnet and we cut the current to it the steel falls to the table, a conversion of gravitational potential energy to kinetic energy until the steel rests on the table again. Have I understood correctly? As an aside, I used to live in Chatham, Chattenden and Maidstone when I was at RSME and serving in the Royal Engineers. I spent a good deal of time at the Historic Dockyard in Chatham, where I drove steam cranes on the docks at the weekends. So I'm quite familiar with the area. That place is very interesting too. If you get a chance to visit the Officer's Mess at the dockyard you can see the vaulted ceiling that was built by ship's carpenters and is really the upside-down hull of a ship.

That wasn't my intention, I was trying to get you to learn before you leap. What do you actually mean by a transducer? Because, as I've previously mentioned, tree's don't think before they open their mouths. Indeed, in the brain as I previously stated, we just don't know which bit does the thinking. Indeed, I'm pretty sure I mentioned dog's and computer's in relation to consciousness, in this thread (if memory serves). But again, it does nothing to bolster your case. What's all this "we" business Tonto, do you have a relevant doctorate?

I was out yesterday (visiting Rochester, on the Medway, a very interesting town with a Norman castle, a c.12th cathedral and a rather fine old high street with a lot of history) so have only just seen this. A permanent magnet has energy in its magnetic field. This energy was imparted when the magnet was first magnetised, aligning the magnetic dipoles of the atoms. A permanent magnet is thus in a metastable, higher energy, state, compared to one that has become demagnetised. What happens when a piece of paramagnetic or ferromagnetic material comes under the influence of this field is a bit complicated but I think in energy terms it is something like the following:- The magnetic dipoles in that material are induced by the field to align with it. This costs energy, relative to the previous field-free, non-aligned state and the energy required comes from the field of the permanent magnet. So there has been a potential energy transfer from the permanent magnet to the material that is being attracted to it. The potential energy of the system can be further lowered by allowing the two objects to move together. It is the stored energy in the field of the permanent magnet that is responsible. (This is made clear when you consider the work you have to do to pull the two objects apart.) But any repeated process involving separating and moving together permanent magnets simply moves energy into and out of the field. Energy can only be extracted from it once, in the phase in which they move together. After this there is no free lunch. Yes I suppose that makes sense. Does it make sense, I wonder, to speak of the radiation distribution having an entropy? What you seem to suggest is that the black body distribution has the maximum entropy of any radiation distribution.

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I once tried building a "perpetual motion" machine not too dissimilar - not because I thought it would work but to work out what I was missing, to understand why it wouldn't. Needless to say it didn't work and I saw the push of magnets equaled the pull, with friction as well.

OK I understand what you mean and I'm aware there is a "magnetic circuit" model used in engineering: https://en.wikipedia.org/wiki/Magnetic_circuit However this has drawbacks if used incautiously, as is in fact mentioned in the article. There is in truth no magnetic "current", as nothing flows. Whilst we habitually draw flux lines with arrows on, these do not indicate a flow of anything. The magnetic field is a vector field, i.e. it has both a magnitude and a direction at any point in space. The density of flux lines is used to denote magnitude and the arrows denote direction. That is all the arrows mean. A field is not a current. (This is explicitly stated in the section of the Wiki article subtitled "limitations".) As for whether this way of thinking of magnetism is a better description, we have just seen how it has given you the wrong answer, in the example of the magnet stuck to a beam. So clearly it has severe limitations. The circuit model may be fine for analysing the shape of the field in electrical machines and so forth but, as with many models in science, it has limits and if these are not borne in mind it can make you look a bit of a berk! 😀 I had not heard of Ed Leedskalnin (not Leedskillin), but I see he was a Latvian immigrant to the USA who was active in magnetism between the wars. I also see that indeed he was on the right track in interpreting magnetism as arising from circulation of charges within the substance, just as I described to you in my previous post. His understanding was thus a foreshadowing of what we understand today about magnetism from atomic theory, quantum physics and quantum chemistry. (Quantum theory was developed in the late 1920s and 1930s, possibly a little later than when he was writing about magnetism.) P.S. Curious fact: magnetism can in fact be shown to arise as a consequence of applying the theory of special relativity to electric charges in relative motion. I think that is rather cool.

Philosophy that ignores science is a Lewis Carroll 'rabbit hole'. And you know what they say of people who assume ...

Do you understand that “fixed” is only an approximation? There is no such thing as a perfectly rigid structure. Which means that the mechanical structure flexes. There are mechanical forces, and they act through a displacement, i.e. they do work. Because that’s involved in magnetic attraction. You have to understand a bit of physics to appreciate the answer. If you don’t, then the answers might look like obfuscation or irrelevance. But you have an obligation here, because demanding an answer that involves a couple of semesters worth of physics, without having that knowledge, isn’t reasonable.

Think about it: the brain is nothing different than electricity flowing through wires. The brain is an electricity-producing machine. That's what we are. And electricity flowing through wires produces magnetism. And maybe, magnetism = consciousness.

For once, we all agree!

Ah, so there's no simple answer to my question, only answers that demand a couple of semesters studying physics and you guys are exercising your right of pedantry and hubris to dodge the question, or, as a layman might put it, you don't know the answer. No problem. So much for "Trust the science". @exchemist, thanks for the civil and helpful replies. The rest of you, meh.

The brain is nothing more than an electronic device. So, every electronic device with a lot of interconnected wires should be conscious too while switched on. We can use a bunch of steel wool and run electricity through it and we should have recreated a small artificial brain. The question is: how do you ask questions to it.