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What is electromagnetic induction? (Part 2)
What is electromagnetic induction? (Part 2)
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What is electromagnetic induction? (Part 2)
15/02/2020 19:32:17 »
Please read the part 1 first:
From the history of electromagnetism it is known that Benjamin Franklin (1705-1790) is the man who was the first to introduce the terms “positive” and “negative”, i.e. “plus/minus” in the field of electricity in the middle of the 18th century. Previously, the different types of electricity had been called “vitreous” (meaning “glass”) and “resinous” (meaning “amber”), since the glass and the amber were the most often rubbed objects to produce the opposite electricities. At the time when Franklin gave his contribution, people had actually spoken of two types of electric fluids; however, Franklin argued that there is only one electric fluid, and the excess and the shortage of it in the objects he called “plus” and “minus”. He said that bodies in normal condition have medium amounts of this fluid and are therefore neutral. When two objects are rubbed against each other, one allegedly transfers a part of its fluid to the other and thus the first becomes minus-, and the second object plus-electrified.
It remains a mystery how this type of thinking resulted in the glass electricity being called “plus”, and the amber electricity “minus”, although it has been recorded that Franklin is the man who assigned the plus to the glass, and the minus to the amber electricity. Still, this cannot be confirmed. In fact, on the basis of this kind of thinking (i.e., in the sense of “excess” and “shortage”) it is impossible to reach a solution, which electricity is plus, and which minus.
[ Edit: this is an older text of mine. In the meantime I found this:
Back then, as well as now, it is still considered to be arbitrary, a matter of convention; therefore it is said that there are no obstacles in naming the electricities the other way round. There exist even such opinions that this de facto should have been the reverse, because the convention is that the electric current through the wire flows from the plus to the minus pole (conventional current), while the electrons, which “appeared” almost one and a half century later and are allegedly the carriers of the electric current, were negatively charged and consequently moving in the contrary direction (electron current), so that with the reversed designation the irreconcilable contradiction, which has since set in motion an “eternal” discussion, would have been avoided. From what we have presented so far, but also from what we are going to expound further, it becomes clear that the polarity of electricities is well chosen and there is no need to change it.
If we look at an image of a magnet with its lines of force in any textbook, we will notice that the directional arrows point outwards at its north (N→) and inwards at its south pole (S←). This should mean that the north pole is the positive, the south pole is the negative. And here, too, it is said in science that it is arbitrary. But since this in no way can be arbitrary, it remains to determine which magnetic pole is actually plus and which minus.
First, let's clarify what is magnetic north pole and what is magnetic south pole. Since we need a compass for that, let us briefly explain what kind of instrument that is. The Earth is a giant magnet with two poles, North and South. They do not quite coincide, but are pretty near to the Earth’s geographic poles. Each magnet, separated from the Earth and free to move, strives to align itself with the giant magnet. To illustrate this, we take a bar magnet and place it on a flat piece of styrofoam. Then we let the styrofoam with the magnet float in a water tank. We will see that however we place it on the water surface, the styrofoam always turns so that the magnet has a strictly fixed direction. If we check the direction, we will find that it is north-south. But not only that. If we mark the styrofoam at one end of the magnet with a red dot, and at the other end with a blue dot, we will see that, in addition to the strict direction, the orientation is also strictly determined: the red and blue ends always place themselves in the same position - one color dot always points north, the other south. Our magnet can only move in a horizontal plane. If it can move in a three-dimensional space, we would see that it is positioning itself in a north-south direction, always tilting at a certain angle to the earth's surface, lowered northwards and raised in the south (this is referred to as the angle of inclination). This we can prove again in our water tank. We take a ball of styrofoam, insert a non-magnetized sewing needle through the center and place the styrofoam ball in water; if the needle does not tend toward to one side, this means that its center of gravity is exactly in the center of the ball. Next, without removing the needle from the ball, we magnetize the needle by touching it with a magnet. When we place the ball back in the water, we notice that the needle except that it turns to where it is in north-south direction, it also dips to the north (that is, it is pointing in our direction if we are facing north). This angle is approximately 45-50° in our latitude. It shows that the needle wants to unite with the magnetic north pole, because it is closer. The further north we go, the greater the angle. It is 90° at the magnetic north pole (the magnetic needle is erected vertically), but at the equator the angle is 0°. We see that the pole of the compass facing north is actually its south pole.
In order to determine which magnetic pole is plus, which minus, the author tried to detect some difference in the jagged shape which tiny iron filings create when they adhere to the north and south pole of the magnet. There seemed to be a difference therein, that at the one pole the spikes looked as if they were single-spiked, and at the other pole they appeared double-triple spiked, similar to the anterior and posterior part of the arrow shape. But it was so unclear and uncertain that one could not rely on it at all. The undoubted result came when the author once played with a ring magnet from a loudspeaker and accidentally came up with the thought of filling the middle of the ring with the iron powder. The poles of the ring magnet are its two flat surfaces. Once its middle was filled with the iron powder and then it was tapped to allow the powder to freely take its shape, the difference between the one and the other side became clearly visible. At the north pole a form of suction was evident, and at the south pole a form of blowing. Hence, the plus pole with an action outwards is the magnetic south pole of the Earth, and the minus pole with an action inwards is the magnetic north pole of the Earth.
The convention in force today is that the pole of the compass pointing north is called the north pole. Hence, the Earth's magnetic pole close to the Geographic North Pole is called the Magnetic South Pole of the Earth, and the one close to the Geographic South Pole is called the Magnetic North Pole. In this work, contrary to the convention, we name the pole of the compass facing north its south pole.
All the confusion actually disappears if the magnetic poles are simply called “plus” and “minus”. The pole of the compass facing north is the plus magnetic pole. The compasses, whose needles have an arrow shape, give a very good picture of this because we term the front part of the arrow, which faces north, “plus”, and the back part, “minus” (− >——> +). [footnote 2]
[ (footnote 2) The front part of the arrow we consider as plus, the back as minus. The front part penetrates and exerts pressure, and the rear suctions, exerts depressure. This can be seen in the shape of the front and the back part of the arrow itself. It is the same with vehicles. Some cyclists risk their lives by driving directly behind large trucks to take advantage of the depressure in the slipstream and reach speeds up to 90-100 km/h on level roads. In videos that can be seen on Youtube, it seems like they are turning the pedals in a void, as if the truck pulls them, although they do not hold onto it.]
We will now introduce a theory which explains what happens in the wire leading to the heart of the transistor, as well as in every current-carrying wire. We call this theory “dynamic” because it speaks of forces (δύναμις = force), in contrast to the current theory, which we call “materialistic” because it speaks of material particles, called electrons, supposedly moving through the metal wires. We call the theory dynamic because in its basis lies vibration of electromagnetic forces (EM-forces). These forces are not of material nature. What was just said is well documented when we recall that the magnetic and the electric forces cannot be blocked by material bodies that are placed between the source of the force and the bodies they act on. For example, if we put a piece of iron near a magnet, the magnet will attract it even if we place a plastic, wooden or metal board between them. Likewise, radio waves penetrate walls without perforating them. This can be done only by something that is not of material nature. But even though they are immaterial, a material body is needed as their source. And in order to manifest themselves, they also need a suitable object to act upon; otherwise we would not be aware of their existence. Actually this is also the case with many other things in life. For example, the painter's abilities are immaterial, but a suitable physical body is necessary as their source. It can be only a human, not a monkey and not a wolf. Still, for these abilities to manifest themselves, they need a material body to act upon, and that is the artist's canvas.
Other terms necessary to understand the theory are “order” and “orientation”. We can get a notion of these terms from several things: from magnetism, thread, wood, etc. When a magnet is brought in the vicinity of iron powder, the particles will adhere to the magnet with strictly oriented order. If we think of such a particle as a very small line segment, then it aligns itself not only in the same direction with the other particles, but also has a strict orientation of its plus and minus poles. We can imagine the particle as the smallest possible line segment and yet its properties will remain as described. In the thread we also have an ordered multiplicity of tiny little plant or animal fibers in the same spiral direction, except that there is no orientation here, that is, the fibers have no poles.
Now we introduce the electromagnetic force element, which is the basis of this theory. We put it this way:
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It has three segments. In the middle is the magnetic segment with its two poles, S(+) and N(–), and at its ends the electrical plus and minus segments, arranged at an angle of 90° to the magnetic segment. We have to imagine these elements in a huge multiplicity, evoked [footnote 3] by the movements of the aforementioned objects (vinyl, glass, magnet) and at the same time ordered according to a strict orientation of their electric and magnetic segments. (Figure below)
inside metal wire.png
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[(footnote 3) For what we call here ‘evoke’ or ‘provoke’, in the current theory is used the Latin verb ‘inducere’, which means "bring in, lead in, introduce". From the explanations in this answer, the reader will understand why we use the verbs ‘evoke’ or ‘provoke’. (Latin=evocare, provocare)]
When there is no movement of the electrified objects towards or away from the wire, we cannot say that these elemental forces are still present in the wire only being chaotically distributed; rather, we should simply say that they are not there, or, to put it more correctly: they are latent. Here we can draw a parallel to the human. If we are offended, it can cause anger in us. Should we then say that the anger constantly exists in us but is, so to speak, only chaotically distributed throughout the body and therefore has no power, and at the moment of offense the chaos get ordered or concentrated and thus develops power? The author thinks that cannot be said. And as the anger of immaterial nature is, so is the hurtful word that has evoked it; for their manifestation, however, material bodies are necessary.
These forces appear not only in the wire, but also in the objects (vinyl and glass) that we rubbed with the woolen cloth. Their electrification can be represented as follows:
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The plus segments of the EM-forces in the glass are directed outwards from the object, the minus segments towards the interior of it, and therefore have no external effect. With the vinyl, it is the other way round.
When we move the plus-electrified object towards the wire, its plus segments evoke the EM-forces in the wire and at the same time arrange them in a spirally whirled form, doing this by acting on their plus segments. The ordered direction of the plus segments in the wire is the same as the direction of motion of the plus-electrified object. Like a gust of wind this effect propagates in a domino effect through the entire length of the wire. Hence, the plus segments of the EM-forces in the wire are oriented to the heart of the transistor, and if it is a plus heart, the lamp lights up. When we move the plus-electrified object away from the wire, it again evokes with its plus segments the EM-forces in the wire by acting on the same-named segments. Because this time the motion is in the opposite direction, the plus segments in the wire are oriented outwardly from its free end. This at the same time means that the minus-segments of the EM-forces are oriented towards the heart of the transistor. If this is a minus heart, then the lamp lights up. The aforesaid also applies to the processes with the movements of the minus-electrified object, only in this case the effects are reversed.
To explain what happens when we insert the magnet into or pull it out of the wire spiral, first we will present the following experiment. Through a thick copper or aluminum tube held vertically we drop a strong cylindrical magnet. We notice that the magnet in the tube falls much slower than out of it. We conclude that in the metal of the tube are evoked the EM-forces whose magnetic segments are so directed that they delay the fall of the magnet. This delay happens from two sides. While the magnet is falling in the tube, its lower end at every moment enters the remaining portion of the tube, and at the same time its upper end leaves the already traversed section. Both the one and the other effect must be slowing down the fall of the magnet; for, if the one slows it down and the other accelerates it, then these two effects would cancel each other out and the magnet would fall with the normal speed. Thus, when the magnet falls down with its minus pole ahead, in the part of the tube which is lower down it evokes the EM-forces whose magnetic segments are oriented with their minus poles upwards, therefore repelling the magnet (i.e. slowing it down); but, in the part of the tube that is higher up than the magnet (where its plus pole is), the EM-forces are evoked in the metal with their minus-poles of the magnetic segments oriented downwards, therefore attracting the magnet (i.e. slowing it down too).
That being said, we return now to the experiment with the spiral wire (which is a kind of a tube) and we can say that the insertion of the magnet into the spiral evokes the EM-forces in the wire by acting on their magnetic segments, which align themselves so that they try to prevent the entrance of the magnet; and that its pulling out evokes the EM-forces, which align themselves so that they try to prevent this, too. But the wire of our spiral is insulated with transparent lacquer, so the metal of the windings cannot touch directly; therefore, the magnetic and electric segments of the elemental forces in the spiral wire are not arranged so to form closed toroidal fluxes below the lower and above the upper end of the magnet (as we can describe the case of the copper tube), but they string together throughout the entire length of the spiral and continue onwards through the straight part of the wire. In other words, the magnetic spiral wind spreads through the entire path of the conductor. The insertion of the magnet with its minus-pole ahead will evoke the EM-forces with their minus-poles oriented outwards of the spiral, however, not at right angles with respect to the wire, but in the upper part pointing to our left, and in the lower part to our right side (thus, in the left part downwards and in the right part upwards) [footnote 4].
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[ (footnote 4) This direction of the EM-forces does not result from some properties of the wire metal, but from the inherent direction of the magnet’s spin. We have here something similar to the push-and-spin mechanisms that we see in small toy carousels, in appropriately designed ashtrays, or spinning top toys. From where we draw the conclusion about the orientation of the magnetic segments in the upper part of the spiral to our left, and not right side, please see my book on academia.edu ]
This again means that the (+)E-segments will be directed to the right, and if the right end of the spiral (the ends facing upwards) goes into the plus and minus hearts of the plus and minus transistors, then the lamp in the plus-circuit lights up. Pulling the magnet out of the spiral will evoke the EM-forces with their (+)magnetic poles facing outwards, therefore the (–)E-segments will be directed to the right, so that the lamp in the minus-circuit lights up. If we now insert and pull out the magnet with its (+)pole ahead, the lamps light up in reverse order.
We can make a similar experiment with an analog or a digital ammeter, but the result with an analog is more impressive. We connect the right end of the spiral to the red (+)input of the ammeter, the left end to the black (–)input. We place the range selector at the highest sensitivity position (mA or μA). The insertion of the magnet with its minus-pole ahead will cause a positive deflection of the pointer (i.e. to the right), while pulling the magnet out will cause a negative deflection (to the left).
What we evoke in the wire with the oscillating movements of the vinyl plate, the glass and the magnet is nothing other than alternating current. The faster we move the objects, the greater the intensity and the frequency of the AC.
P.S. On this forum it is not allowed more than 20000 characters per thread, so please read the part 3 at this link:
Last Edit: 16/02/2020 07:55:42 by
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