The Naked Scientists Forum
On the Lighter Side
A Theory of Magnetic Induction
A Theory of Magnetic Induction
0 Members and 1 Guest are viewing this topic.
A Theory of Magnetic Induction
11/03/2016 11:46:32 »
A Theory of ‘Magnetic Induction’.
The ability of a magnetic field to induce a current in a wire is one of the more remarkable phenomenon of physics. It happens every time a conducting material is passed through a magnetic field or vice versa, but what exactly is the ‘mechanism’ that induces a current in a wire and what causes the emergence of the magnetic field loops that surround a current carrying wire?
The creation of a magnetic field around a current carrying wire owes its presence to the property of the electron known as its ‘magnetic dipole moment’. This ‘magnetic dipole moment’ is often referred to in the literature as being ‘anomalous’ because its presence cannot be adequately explained, but it exists and not only upon electrons, but also upon the proton and the neutron.
The fact that the electron has a ‘magnetic dipole moment’ implies that it must have a magnetic field and if there is a magnetic field present, then there must be a magnetic source generating it. The inference from this is that the electron functions like a ‘tiny permanent magnet’.
If this concept of the electron as being the source of a magnetic field is unacceptable to you, then there is little point reading on, except perhaps for curiosity as to what it implies.
The implication of the ‘magnetic electron’ is that it can explain the quantum nature of a magnetic field and the presence of circulating magnetic field loops, both upon a ‘micro scale’ around the electron and a ‘macro scale’ around a current carrying wire. The term ‘circulating’ is used advisably here rather than ‘rotating’, as magnetic loops do not rotate, they travel in a circulating mode to create their own field loop.
The magnetic field loops around a current carrying wire are visibly demonstrated by the iconic ‘iron filings’ experiments and being loops, they are finite in their size. The electron’s magnetic dipole moment is the source of these magnetic loops and as there are a finite number of electrons in a wiring circuit or a permanent magnet, then there are a finite number of magnetic loops in a magnetic field. The implication of this is that all magnetic fields are ‘quantum entities’, with their ‘field reach’ determined by the longest magnetic loop in the field. No loops travel to infinity!
Magnetic field loops ‘circulate’ in a clockwise direction around a wire in the direction of the current flow and anti-clockwise if the current flow is reversed. The clockwise and anti-clockwise ‘circulating field loops’ are a unique feature of magnetic fields and is the ‘characteristic’ that creates both the ‘attracting’ and ‘repelling’ forces of magnetism.
There is no such thing as a magnetic field loop which has a north and south pole! It either circulates clockwise or anti-clockwise.
Magnetic field loops also have the ability to penetrate through matter as if it didn’t exist. They can never be ‘absorbed’ or ‘destroyed’. This is amply demonstrated by the earth’s magnetic field, whose loops travel some four thousand miles from the centre of the earth to the earth’s surface, before looping back again to the core. It is a remarkable demonstration of ‘penetrability’, exceeding even the neutrino’s capability. Why is this important? Because magnetic field loops can pass straight through plastic coated copper or iron wiring.
However, the path of a magnetic field loop can be deflected by the presence of another magnetic field or an encounter with a medium that is susceptible to the flow of magnetic flux and these obstacles force the loops to re-route themselves along a different pathway. Once clear of the deflecting obstacle, magnetic field loops will always return to the original path of their loop, even if the diversion has forced them down a much longer route.
The explanation of this is simply that the deflected loops are all still part of a magnetic field and as magnetic field loops cannot cross each other, the deflected loops are always constrained by their outer and inner magnetic field loops into returning back to their original pathways.
The implication of this finiteness, is that each magnetic loop must have a larger or smaller diameter than its immediate neighbours in the field by a ‘finite amount’. Without this differentiation, the loops would cease to be quantum entities and the magnetic field would devolve into a continuum, thereby breaking one of the basic rules of magnetism, that “magnetic lines circulating in the same direction repel each other”.
If you don’t accept the quantum nature of a magnetic field, then the reasoning that follows is fatally undermined, but if you just haven’t thought of a magnetic field in the context of quantum theory, then read on.
The finite nature of a magnetic loop around a current carrying wire or around a permanent magnet and its ability to rotate clockwise and anti-clockwise needs an explanation and this is met by the concept of a quantum of ‘magnetic energy’ (meq), which circulates perpetually around its magnetic field loop without energy loss.
This concept is again fundamental to the arguments that follow, so if you dismiss it, then don’t read on. But perhaps first you can reflect upon your own explanation as to how magnetic loops attract and repel each other and if any doubts arise, read on for interest.
The magnetic energy carried within a magnetic field loop is always a fixed amount, just as Plank’s constant is for the energy carried by a single photon. But for magnetic field loops, it is the circumference of the loop that determines the frequency of circulation. This ‘circulation frequency’ also determines the strength of the magnetic field at any point on the loop. Increase the loop circumference and the field strength falls off inversely with the increase, simply because the ‘magnetic energy quantum’ follows an incrementally longer perimeter pathway.
The opposite is true for reductions in the loop circumference leading to an increase in field strength. Looking at a magnetic field is a bit like looking at the spectrum of light, but seeing all the wavelengths at the same time.
From the perspective of the ‘electron’, the perimeter of its circulating loop of magnetic energy not only determines the magnitude of its ‘magnetic dipole moment’, but it also determines the electron’s wavelength. And if the ‘magnetic energy quantum’ (meq) of its field loop circulates clockwise around the orientation of the electron’s core, then the electron is said to be in an ‘up spin’ state and if it circulates anti-clockwise with the same orientation, the electron is said to be in a ‘down spin’ state.
With this model of the electron in mind, as a ‘particle-wave’ entity, having a quantum of magnetic energy circulating around its magnetic core, then the tools are in place to develop an explanation for the creation of the nested magnetic loops around a current carrying wire and subsequently the phenomenon of ‘magnetic induction’. But the first step towards this is to define what an electric current in a wire actually is.
The concept of an electric current has been regarded in the past as the physical flow of electrons around a wired circuit. But electrons in a wired circuit don’t move fast enough or far enough along a wire to achieve the near instantaneous transfer of energy that is seen in practice, for example, when flicking the switch in a lighting circuit. This leads to the concept of the energy flow from the generating source around a wired circuit as being a ‘vibrational phenomenon’ between electrons.
The retention of the ‘free electrons’ within their orbits around the nuclei during the passage of a vibrational current, enables the wire to retain its structural integrity during the transmission of the current. The wire only fractures when it becomes hot enough to physically eject electrons, as happens, for example, with the filament of a tungsten light bulb.
Charging up the ‘generating mechanism’ of an electric current, such as: a battery, dynamo or solar panel, requires the physical or chemical removal of electrons from their locations in the atom or molecule. The electrons are then either ‘free to flow’ or are ‘cached’ upon an insulator or insulated conductor. But what is inferred rather than explained, is where and how the electrons store this energy, when they are removed from their location around the nucleus of the atom.
This removal of the electron from the influence of the nucleus of an atom is the same process as separating two magnets. The particles disconnect their magnetic field loops and become independent magnets again, with the work done to separate them being stored as smaller but more ‘energetic loops’. This ability of the ‘magnetic field loops’ of two magnets to disconnect from each other when pulled apart and then to re-connect when brought back together again, is another unique characteristic of magnetic fields, which is called ‘magnetic re-connectivity’.
In order to create the magnetic field loops around a current carrying wire that gives rise to the phenomenon of ‘magnetic induction’, the electrons in the wire need to be ‘energised’, although the terminology often used in the literature to express this state is ‘excited’. What is meant by the term ‘energised electron’ is that the electron has taken on an additional quantum loop of ‘magnetic energy’ circulating around its magnetic core.
Just as an ‘energised electron’ can release radiant energy quanta from its location within the atom, so the energised electrons from the ‘generating source’ release loops of ‘magnetic energy quanta’ into the wired circuit, before falling back to their ‘ground state’. The ‘conduits’ in the wire that facilitate the flow of these ‘magnetic energy quanta’ (meq) are the ‘free electrons’, which are situated in the outer shells of the atoms. All the atoms in the conduits are located in straight lines along the array nodes, this being a defining feature of the crystalline structure of a metal conducting wire.
The input of the ‘meq loops’ from the generator into the conduits of the wire, energises each of the free electrons in turn as it is propagated along the wire. The process creates a ‘vibrational effect’ between neighbouring electrons, analogous to how sound travels through air. By this means the generator’s energy packages are transmitted rapidly along the conduits of the circuit. An important point about this vibrational interaction between the magnetic loops of the free electrons along the wire, is that there is no energy loss incurred by their transmission from the generator to the load.
The vibrational transmission of magnetic energy quanta is constantly repeated as the generating source releases a fresh input into the circuit and the process continues until the battery runs down or in the case of a solar cell, the sun stops shining.
However, there are two side effects of this process, the first being radiant energy emission and the second being the appearance of magnetic loops around the wire.
If the vibrational process is impeded by any fault in the wire, for example from a variation in thickness of the metal wire or an impurity in the metal wire or even an ionised atom, but particularly by the flipping of electrons from one spin state to another, then these faults and spin inversions in transmission, cause the energised electron to release photons, creating the heating effect in wires.
The creation of the nested magnetic field loops around the wire, happens in a more ordered way, by a process which is analogous to stroking an iron bar with a permanent magnet. Although in this case, it is the incoming ‘magnetic energy loops’ from the generating source that play this role, by lining up the ‘magnetic loops’ of the ‘free electrons’ in a common orientation and spin state along the wire and this reorienting process causes the wire to function as if it were a ‘permanent magnet’.
Just like a permanent magnet, the ordered electron meq loops head out into the spaces between the atomic arrays of the metal wire and from there are channelled by the magnetic fields of the atoms towards the surface of the wire. Once free of the wire, the ‘meq loops’ have no other option but to circulate around the wire within the plane from which they have just exited. Each new meq loop forces an already established loop to incrementally expand its diameter to accommodate it, which leads to the orderly ‘nested loop structure’ of the magnetic field in perpendicular planes around the wire.
The number of concentric loops in a perpendicular plane around the wire, is determined by the number of free electrons that are located in the array of atoms contained within each ‘cross section’ of the wire. This nested loop structure of the magnetic field generated by the current flow along the wire, then continues to exist just as long as the ‘magnetic energy loops’ are being transmitted from the generating source, keeping the wire magnetised.
The ‘magnetic induction’ of a current in a secondary wired circuit occurs in a similar manner to the primary wire, but for the secondary wire, the growing magnetic field of the primary circuit takes on the role of the battery by energising the free electrons all along in the secondary circuit. The growing number of meq loops that pass straight through the secondary wire, energise and re-orientate the spin state of the free electrons as they pass. This energisation of the free electrons in the secondary wire creates the same vibrational effect as the primary wire experienced from its generating source and this is transferred along the secondary wire as a brief burst of induced current.
But, just as the primary wire established its magnetic field, so the induced current flowing in the secondary wire creates its own magnetic field of circulating magnetic loops around itself. This creation of a magnetic field around the secondary wire results in the primary wire’s magnetic loops being deflected to skirt around the secondary wire’s magnetic field. This deflection of the primary wire’s meq loops, leads to an immediate cessation of the current in the secondary wire and the induced current falls back to zero.
The magnetic field of the primary wire still maintains its meq field loops in their deflected pathways and this status quo is only changed when the primary wire’s current is switched off. With the demise of the primary current, the primary field’s meq loops return to the primary wire and with no magnetic field around the secondary wire to deflect them, they do so by returning to their original pathways within their own magnetic field and their meq’s pass through the secondary wire once again, creating another fleetingly induced current in the secondary wire’s circuit, albeit in the opposite direction.
The magnitude of the induced current in the secondary wire always depends upon the number and strength of the primary field loops that pass through it. The direction of flow of the induced current is determined by the circulatory direction of the primary current’s magnetic field loops. If the field loops are experienced as circulating clockwise they transmit the secondary vibrating current one way and if they are experienced as circulating anti-clockwise, they send the vibrating current the opposite way.
The essence of this explanation of magnetic induction, rests upon three concepts: the ‘magnetic electron, the ‘quantum magnetic field’ and the circulating ‘magnetic energy quanta’. However, I suspect that most readers will be thinking: “What about the concept of electric charge!”
My reply is simply to say to you, “Is the concept of an electric charge germane to this explanation of magnetic induction?”
Last Edit: 12/03/2016 12:27:39 by RTCPhysics