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IATF
IATF said:So I am very much keen on the question that can magnets produce force without losing any energy?
Isn't that the reason magnets are supposed to be stored in a certain arrangement, to avoid "weakening" them?Charles Link said:One thing that would seem to be the case is if two like poles are brought in close proximity that the magnetization would be reduced somewhat by the strong field in the opposite direction being superimposed on the strong magnetic field and strong magnetization inside the other magnet.
Mostly for the OP: The energy equations involved in these processes is also something that doesn't seem to be spelled out in simple form in any elementary literature that I have seen=perhaps because the complete energetic gets somewhat complicated. In more advanced E&M coursework, they teach what the energy density is for a magnetic field. In the case of the permanent magnet it gets more complex though, and if I'm not mistaken, the permanent magnet is actually in a state of lower energy than the unmagnetized state. The magnetized material (magnetic moments) in its own magnetic field, basically generated from bound magnetic surface currents from the magnetization, results in a lower energy state than the unmagnetized state. Because it is a lower energy state, the permanent magnet state can be extremely stable in many cases, but bringing magnets together with like poles facing each other could potentially disrupt the permanent magnetized states. ## \\ ## Instinctively, one would conclude, correctly so, that there must be some energy of some kind associated with the magnetic field. The complete dynamics of that in the case of the permanent magnet can get somewhat complex. What further complicates the matter is even in the less than fully magnetized state, there are microscopic domains that individually can be completely magnetized, but they can point in somewhat random directions in non fully magnetized material. I don't want to get "pinned" for a personal theory which is not allowed according to Physics Forums rules, but I believe it is some complicated energetics of this kind that makes the difference in whether a magnetic material becomes a permanent magnet, as opposed to materials like soft iron that make very good electromagnets, but become unmagnetized once the external magnetic field is removed.jerromyjon said:Isn't that the reason magnets are supposed to be stored in a certain arrangement, to avoid "weakening" them?
It does help to understand that every magnetic atom has some relative position, when they are randomly opposed equally there is no net magnetic field generated... it's not like the individual atoms lose energy, ever.
IATF said:How much complex is Quantum Mechanics!
IATF said:If my friend and me try to push one another, we are going to lose all of our relish within a minute; but that's not the case with magnets.
IATF said:Don't you think we can use this never-ending force in generating energy.
IATF said:I really have a brilliant idea for its progress, but that is beyond the scope of this website.
IATF said:Sir Drakkith, Brillant discoveries are only a result of working on impossible, and I'm doing so.
IATF said:So I am very much keen on the question that can magnets produce force without losing any energy?
a modern samarium-cobalt magnet takes around 700 years to lose half its strength.
I do notice, however, that an electromagnet stores energy in its magnetic field, and we can easily extract it by switching off the current.CWatters said:Magnets are not a source of energy
Working on the impossible seems impossible to me. Do you perhaps mean :IATF said:Sir Drakkith, Brillant discoveries are only a result of working on impossible, and I'm doing so.
An analysis of exactly how "a magnet ... is used to magnetize another piece of metal" will reveal the answer to you.IATF said:Will a magnet still retain its energy if it is used to magnetize another piece of metal with its magnetic field?
Yes I should have been clear ideas referring to permanent magnets.tech99 said:I do notice, however, that an electromagnet stores energy in its magnetic field, and we can easily extract it by switching off the current.
You can use a magnet to magnetise another piece of metal as often as you like and your original magnet will be as strong as if you had not done so.*IATF said:Will a magnet still retain its energy if it is used to magnetize another piece of metal with its magnetic field?
Merlin3189 said:Contrary to some earlier comments, I would say magnets can be used to generate energy - provided by generate we mean convert energy from one form to another. I have three generators built with permanent magnets, one on my bike and two on torches. They all work the same way: when i put energy in by turning them, the magnets inside move and generate an electric voltage in a coil. This can then make a bulb or LED light up. The magnets will work indefinitely* in these machines and do not use up any energy of their own: they take the energy I supply as movement and pass it on to electrons to give the electric current.
It's not quite that dire. If you've studied single-variable differential and integral calculus before you start college (not at all unusual) it is quite reasonable to start in on QM in the second semester of the second year.Drakkith said:It requires about 3-4 years of intense study at a university before you can even begin to study QM in a way to gain a good understanding.
The magnetic field is by definition the part of the force that does not perform work.IATF said:How much complex is Quantum Mechanics! If my friend and me try to push one another, we are going to lose all of our relish within five minutes; but that's not the case with magnets. Don't you think we can use this never-ending force in generating energy?
But force can do work, and energy is the ability to do work isn't it? Doesn't force come from energy?russ_watters said:A month? Really?
Force isn't energy, so there is no reason exerting a force should require expense of energy.
Yes. "Can". But they don't have to.Garfunkel said:But force can do work...
Yes.and energy is the ability to do work isn't it?
No.Doesn't force come from energy?
Magnets repel each other due to their polarities. Like poles (north and north or south and south) will repel each other, while opposite poles (north and south) will attract each other.
Yes, they will. When 2 magnets repel each other, they are doing work against each other, and this work requires energy. As a result, the energy of the magnets will decrease over time.
No, they cannot. As mentioned before, the energy of magnets decreases as they repel each other. Eventually, the energy will reach a point where it is not strong enough to overcome the attractive forces between the magnets, and they will come together.
Yes, the energy lost when magnets repel each other can be recovered. This is known as the conservation of energy principle. The energy may be converted into other forms, such as heat, but it is not completely lost.
The repelling force between magnets decreases as the distance between them increases. This is because the magnetic fields of the magnets weaken as they move further apart, making it easier for the attractive forces to overcome the repelling forces.