What is electromagn...
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[Sticky] What is electromagnetic induction?  


Mitko Gorgiev
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Joined: 3 years ago
Posts: 41
22/12/2019 10:17 pm  

Electromagnetic induction is the process of producing electric and magnetic current in a metal wire by:

1) a moving electric field / an electric wind
2) a moving magnetic field / a magnetic wind.

I will begin this post from far away, but please stay tuned, I will come to the point and I assure you that you will learn something new.


We all breathe. Animals breathe too, and plants also breathe in some way. What is breathing? An initial observation could tell us that breathing is a constant expansion and reduction - a pulsation: when we inhale, our chests expand; when we exhale, they reduce in size.

The first two arithmetic operations a child learns in mathematics are addition and subtraction. If we add two to five, in reality it may mean that something that fills five volume units now expands by two and fills seven units. In turn, subtracting two out of seven means that seven contracts by two units and then fills five volume units. Therefore, we can label the expansion with the sign ‘+’ and the contraction with the sign ‘–’. In this way, the act of inhaling we evaluate with plus, the act of exhaling with minus. In mathematics we can play through various computational tasks that often have nothing in common with our real world; but, if we want to stand on the ground of physical reality, we have to say that for each plus, a minus have to simultaneously arise somewhere. When we inhale, it means a plus in our chest at the expense of the surrounding atmosphere, which suffers a minus. This can be seen more clearly when we are inflating a balloon. The balloon is expanding, it means a plus arises within; but, at the same time, our chest is reducing, there is a minus in it. Let us take another example. A vacuum cleaner performs suction (–), but at the same time there is a vent on its plastic covering through which the air goes out (+). With a hair dryer we have the reverse.

Both the vacuum cleaner and the hair dryer are actually propellers (fans). The observer who stands in front of a fan will say that it blows, i.e. it exerts pressure (plus action), while the observer standing behind the fan will say that it suctions, i.e. it exerts depressure (minus action). In general, we could say that the plus denotes an action outwards, the minus denotes an action inwards (figure below).

Let us now consider a fan with only two blades. If the blades are completely flat, then, when the fan is turning, they will only cut the air like knives and there will be neither blowing nor suctioning. For this fan to function, it is necessary to twist the blades to a certain degree in the following way:

When this electrically driven fan, whose blades are twisted to the left, begins to turn to the right, then standing in front of it we will feel pressure, i.e. that it blows us (+); while, when it turns to the left, we will feel depressure, i.e. that it suctions us (–). If we twist the blades in the contrary direction (to the right), then at the turning of the fan to the right, we feel depressure (–), while at its turning to the left we feel pressure (+), or the reverse of the previous case [footnote 1].

[ [footnote 1] Regarding the twist of the blades, the reader should think of wringing out a wet towel. If the right hand turns to the right, then we say the towel is twisted to the right; if it turns to the left, the towel is twisted to the left. The same applies to the fan blades.
If we are to predict whether a fan will blow or suction if it starts turning to the right, first we need to look at the twist of the blades. If the blades are twisted to the left, i.e. like this ‘/’ (fan blade viewed from above), then, when this blade turns to the right, it attacks the air first with its ‘upper’ part. Higher air pressure forms in front of this part than in front of the ‘lower’ part, so the air moves towards us, i.e. we are blown. What is important here to us for that what follows is to pay attention to the fact, that the blades of a fan (if it is a multi-bladed) which at a given moment are up blow us more on our left side, and those which at the same moment are down blow us more on our right side; that is, the flux is whirled rather than linear.]

We see that for an observer, whose position remains unchanged (i.e. standing in front of the fan the whole time), the following four cases may occur:

Look at the broken circles on the figure below. As you move the book closer and then farther away from you, looking constantly at the central point of the circles; or, if you place the book on a table, then lower and raise your head still looking at the central point (in this case the effect is stronger) - it seems as if the circles are turning in one direction upon coming closer, but in the contrary direction upon moving away. The experiment can also be carried out with only one circle. The dashes of the outer circle are ‘twisted’ to the left, those of the inner circle to the right. Upon moving the head closer, the outer circle turns to the left, the inner one to the right. When moving away, the opposite occurs. What does the movement away mean? It means nothing other than that the circle is ‘blowing’ at us, just as with the approaching of the head the circle draws us in. We see that we have here exactly the same conditions as in the previous case of the fans, so that the table above is valid here too.

[ The outer circle corresponds to the fan described in the text box above. When we move our head away, i.e., when it ‘blows’ at us, then it turns to the right.
The turning effect comes about only if the circles’ dashes are somewhat slanted.]

Let’s consider these two spirals:

They differ only therein, that the first turns to the left (observing the black line from the center outwards), while the second to the right. If we make holes in the centers of the spirals, place them on spinning tops and turn the first one to the right looking unremittingly at it as it rotates, then we have the feeling as if it exerts pressure on us, i.e., as if it were pushing us (+), whereas when turning it to the left, we have the feeling as if it exerts depressure on us, i.e., as if it were pulling us in (–). With the second spiral occurs the same but in reverse order. We see that for an observer arise the same four cases from the previous table. (The spiral line turns to the left, the spinner turns to the right - then the spiral pushes us (+). This case corresponds to the fan’s case described in the frame above. The same occurs with a screw or a household meat grinder. The thread of the screw turns to the left, and as the screw is turned to the right, it penetrates (+) into the wood.)

Let's go back to the fan again. Instead of an internal drive setting it in motion, it can also be turned by an outside force, as is the case with windmills. To see what happens here, we will make a simulation with a small fan (like those in computers), a hairdryer and a vacuum cleaner. If we bring an operating hair dryer close to the fan, it starts turning in one direction, and upon bringing an operating vacuum cleaner, it rotates in the contrary direction. The reverse happens if the fan blades are twisted in the contrary direction. There are four cases also here, two pluses and two minuses.

Everyone knows that something called ‘plus’ and ‘minus’ exists in both electricity and magnetism. We have all seen that ordinary 1.5V batteries have the mark (+) at the nipple and the mark (–) at the flat end. In magnetism, the two poles are called north and south, but they can be rightly called plus and minus. Which pole is here plus and which minus, we will see later. Do these plus and minus poles of electricity and magnetism show properties reminiscent of those we have just seen? To test this, we will carry out some experiments. Therefore we need two simple, almost identical electrical circuits, each with a battery, a resistor, an LED lamp and a transistor (figure below).

The circuits are independent of each other and do not differ absolutely in anything other than in polarity. What that means will be clear in a moment. The lamp serves as an indicator. When it lights up, it means that current is flowing through the circuit. The resistor (300Ω - 1kΩ) is solely in the service of the lamp, to prevent a stronger current causing damage. What remains is to briefly explain the element called transistor. Unlike the majority of elements in electrical technology that have two ends, i.e. two leads, this element has three ends, because internally it consists of three segments (figure below).

About the transistor we will now figuratively say only what we need for the experiments, but will explain more later. What matters most to us at the moment is its middle segment, which we will temporarily call a heart of the transistor. In the drawing we can see that the left transistor has a plus-heart (we call it + transistor), while the right one has a minus-heart (– transistor). We also see that the heart is a kind of bridge between the other two segments. In order to make the (+)transistor work, its heart should be actuated by (+)electricity. Thereby the bridge is established. If the heart is acted upon by (–)electricity, then it behaves indifferently. The reverse applies for the (–)transistor.

The lead from the heart we lengthen with a metal wire that is several or even many meters long, thus its end will be far from the circuit itself. Therefore we will be absolutely sure that the influence we are going to exert on the end of the wire affects only it and not any other element in the circuit. The end of the wire is loose, that is, not connected to anything.

However, in order to check what we have just said, that the (+)heart reacts only to plus-electricity, whereas the (–)heart to minus-electricity, we may hold the loose end of the wire with one hand and with the other hand first touch the (+)pole of the battery and then the (–)pole. We will see that the lamp lights up only in one of the two cases: in the (+)circuit [the circuit with the (+)transistor we will call (+)circuit] the lamp lights up only when we touch the (+)pole of its battery; and in the (–)circuit it lights up only when we touch the (–)pole of its battery. It is not advisable to connect the end of the wire directly to the (+)pole of the battery in the first case and to the (–)pole in the second for reason explained later in this paper.

What will be described now as an experiment can be done with these circuits’ set-ups; however, for their greater sensitivity, in each of them we will add one more transistor [two (+)transistors in the first and two (–)transistors in the second circuit (figure below)]. It doesn’t change anything except that we will save on effort needed to do the experiment, i.e., with less effort we will achieve a greater effect. If we still work with only one transistor per circuit the effect will be weaker, but it can be somewhat intensified if we attach the loose end of the wire to a wide metal plate - let’s say a pot lid - and if we reduce the resistor’s value to 100-200Ω.

Once the two circuits are ready, we take a vinyl gramophone plate, a thin-walled glass, and a piece of woolen and silk fabric. We rub the vinyl plate with the woollen cloth and bring it close to the loose end of the wire of the (–)circuit. We will see that the LED will light up. It will also light up if we bring it close to the wire’s loose end of the (+)circuit. But if we play a little bit, we will notice that there is a fundamental difference between the two cases: the LED in the (–)circuit lights up when we move the vinyl plate towards the wire, and the LED in the (+)circuit lights up when we move the plate away from the wire. Now, if we take the glass, rub it with the silk (or woollen) cloth, we will notice that the reverse happens: the LED in the (–)circuit lights up when we move the glass away from the wire, and the LED in the (+)circuit lights up when we move it towards the wire. If we don’t move the electrified objects, absolutely nothing happens. As mentioned before, this is quite feasible with only one transistor per circuit, yet the movements of the vinyl plate and the glass have to be much more energetic. But even in this experiment with two transistors per circuit we can notice that the faster we move the electrified objects, the stronger the lamps light up.

The cloths after the rubbing produce the reverse effect from the rubbed objects. Still, their effect dies out much faster than that of the vinyl plate and the glass.

From this it becomes clear that vinyl and glass act completely opposite: vinyl stimulates the minus transistor by moving towards, and glass by moving away from the wire end; vinyl stimulates the plus transistor by moving away from the wire end, glass by moving towards it. We see that there are four cases here as well:

Let’s carry out another experiment with these two circuits. We take a long isolated wire, wind it around a cylindrical object and then remove it, thereby obtaining a spiral-shaped wire. We connect one end of it to the two loose ends of the wires leading to the transistors of the (+) and (–)circuits (here, as before, we can do the experiment with only one circuit at a time). The other end of the spiral wire remains loose. Now we take a strong cylindrical neodymium magnet and quickly insert it, keep it inside, then quickly pull it out of the spiral. We notice that one lamp lights up upon inserting the magnet, while the other lights up upon pulling it out. As long as the magnet remains in the spiral, nothing happens. Then if we turn the magnet, insert it and pull it out with its opposite end ahead, the lamps light up in reverse order. They light up more strongly if the magnet is inserted and pulled out faster, if the spiral has more windings, if the magnet is larger and stronger, and if its diameter is not much smaller than that of the spiral. For this experiment to be carried out successfully as described here, we need a very strong magnet, many windings and very quick insertion and removal from the spiral. If these conditions are not fully met, then we don’t leave one end of the spiral loose; instead, we connect it to the (–)pole of the battery in the (+)circuit, and to the (+)pole of the battery in the (–)circuit; thereby the experiment is carried out much more easily. We see that there are four cases also here.

That the positive electricity has the nature of expansion (blowing, pressure, explosion) and the negative electricity the nature of contraction (suctioning, depressure, implosion) can also be seen with naked eye. There is namely a whole group of so-called electrostatic generators, also called influence machines, similar but somewhat different from each other: Voss-, Toepler-, Holtz-, Bonetti-, and the most popular and widespread, the Wimshurst-machine. Since this machine is available to us, we will briefly describe it. The basic elements of this generator are two very close (about 5 mm), vertically placed glass or plastic circular plates (discs), metallic sectors of aluminum foil glued on the discs and two metal rods placed in the shape of the letter X, but one in front of the front disc (\), and the other behind the rear disc (/). Although the rods are on different sides, we will say that their X-shaped placement divides the discs into quarters, which we will call quadrants. We term the left and the right one horizontal quadrants, the upper and lower one vertical quadrants. The metal rods, which have the shape of the square bracket “]”, end with metal brushes that gently scratch the plates (including the metallic sectors) when the discs rotate. They rotate in contrary directions; this is achieved so that during the manual rotation of the crank, the movement is conveyed by two belts, one of which (for the front disc) is in the form of the letter O, and the other (for the rear disc) is twisted in the shape of number 8. Electricity is generated solely by these elements. Therefore we consider the other parts of the machine as inessential. They are necessary only if we want to produce sparks from the already generated electricity; so, to prevent them from bothering us, we can even remove them. We will consider them later.

If we begin to rotate the discs by turning the crank to the right in a dark room (the most noticeable results can be seen at night in a room with a little exterior street light entering it), and if we do this for at least 10-15 seconds to let the eyes get used to the feeble light, we will notice that the horizontal quadrants emit a light flicker, whereas the vertical are completely dark. On turning the crank to the left the flicker relocates to the vertical quadrants, whereas the horizontal ones now remain dark. Looking even more attentively at the scene, we will notice an essential qualitative difference between what happens in the left and the right quadrant (i.e. the upper and the lower one when the crank is turned to the left). The flicker in one horizontal quadrant is directed from the metal sectors outwards, in the other one inwards. In other words, in the left quadrant the metal sectors are dark and the flickering light glows around them, but in the right quadrant the metal sectors are illuminated and around them it is dark (image below).

The sectors in the image are drawn as a whole, and not individually, because the light phenomenon appears as a whole; more precisely, as two wholes, one left and one right, and not individually in the sectors. We consider this as an ultimate proof of the essential difference between the plus and the minus of the electricity. We say that a proof is ultimate or final when we directly perceive the truth with our senses.

Without turning the generator, we move the wire of the (+)circuit with its loose end towards, and then away from one horizontal quadrant; then we do the same with the other quadrant. We can do also the reverse: move the generator with its left or right quadrant towards and away from the wire (as we did with the vinyl plate and the glass), which is basically the same. With the left quadrant, where the flicker was directed outwards, the lamp lights up only when the wire moves towards it; with the right quadrant the lamp lights up only when the wire moves away from it. If we do the same with the wire of the (–)circuit, then the reverse happens. We see that the (+)quadrant behaves like the glass, while the (–)quadrant like the vinyl plate.

Observing the described phenomena in the dark, we find that we don’t actually need any detector to determine on which side is the plus-, and on which side the minus-electricity.

Whether the plus will appear in the left, and the minus in the right quadrant, or the reverse will happen, is left to chance. The plus and the minus may occasionally change sides.

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.

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 strictlyoriented 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:

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)

[(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:

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 elemental 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 wireby 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]. (Figure below)

[ (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. Please see also Inducing electric current in a wire by moving magnetic field.
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 ]

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). The same experiment made with a digital ammeter will show a minus sign in front of the digits upon pulling of the magnet out.

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. But it can also be said that we produce what in digital electronics is called one (1) and zero (0). When the plus electricity is directed to the hearts of the transistors, it is a digital “1”, when the negative electricity is directed that way, it is a digital “0”. Or briefly: the (+)electricity is 1, the (–)electricity is 0.

• • • • •

Although very simple and at the same time very important, the experiment with the glass, the vinyl and the transistors’ circuits performed in the way presented is yet not known, although it could have been carried out long ago, even when no transistors existed. How? Very simple, with the help of an electroscope.

Please look at the drawing below. In the middle is a gold leaf electroscope (nowadays the gold leaves are replaced with aluminum foils), from the top of which two metal wires, many meters long, are drawn. The wires extend in opposite directions, thus making their ends very far apart. Thereby the interference of the different influences on the wires, carried out during the experiment, will be avoided.

If we now move the electrified glass toward the end of one wire, then the leaves will spread apart. They spread apart because a positive current flows through the wire and the moment it reaches the other end, it electrifies the air around the leaves. This air-electrification keeps the leaves spread. Now we move the glass away from the wire. The leaves join together. Why? Towards the opposite end of the wire now flows a negative current which is electrifying the air negatively, that is, it is neutralizing its previous positive electrification.

Now we move the glass object again toward the wire. The leaves spread apart. Then we touch the top of the electroscope with a finger, neutralizing the air-electrification in the electroscope and the leaves close together (this "neutralization" requires further explanation of what exactly is going on, but that will be left for another answer). The glass object remains stationary in the immediate vicinity of the wire. Then we move the electrified vinyl plate toward the end of the other wire. The leaves spread apart. Now we move the glass object away from the end of the first wire. The leaves spread apart even more. Why? By moving the positively electrified glass away we caused a negative current toward the opposite end of the wire, further intensifying the previous negative electrification.

By moving the vinyl plate and the glass toward or away and by touching the top of the electroscope, we can perform other variations of the experiment, too.

• • • • •

When we move a hand-held fan, then we cause an air-wind. Just as a higher pressure/blowing is created in front of the fan (plus) and lower pressure/suctioning behind the fan (minus), so it is created a plus-electricity (blowing) in front of the electrified glass object and minus-electricity (suctioning) behind it when we move it. The difference between the two cases is that with the electricity we can also move a negatively electrified object, whereby the minus-electricity (suctioning) is created in front of the object, while the plus-electricity (blowing) behind the object.

So, the electromagnetic induction is evoking electric current in a metal wire by:
1) moving electric field to or fro the wire longitudinally (by acting on the E-segments);
2) moving magnetic field to or fro the wire transversally (by acting on the M-segments).

This post needs to be extended with an explanation of another case of induction as that in the transformers. Here twisting and untwisting of the magnetic field takes place. But I will explain that in another post.

Please read also What is an electrical current?

P.S. Consider also the following experiment: from a lacquered copper wire we cut off twenty to thirty pieces of about 10 cm. From them we form a bundle of parallel wires and connect the two ends with one more wire each. The other ends of these two wires are connected to a sensitive analog ammeter. We hold the bundle horizontally and move quickly a strong and broad magnet downwards on its left side. The pointer of the instrument will make a deflection to one side. If we now move the magnet quickly downwards on the right side of the bundle, the instrument will make a deflection to the opposite side. The magnetic flux that we have produced in the wire is now in the opposite direction to the one in the first case, which is why the deflection is in the opposite direction. The motion of the magnet produces current even if we only approach it to the bundle from one side without lowering it below the bundle. In this case the current is somewhat weaker. But if we now move the magnet down to the middle of the bundle, the instrument won’t show any current, because the left and the right halve of the magnet act on opposite sides of the bundle, canceling each other out.
We can do the experiment with only a single wire instead of a bundle, as long as we have a very strong magnet and a very sensitive ammeter.
You can imagine that inside this wire there is a propeller or there are many propellers in a row. When you turn a propeller manually from the left side, then it is turning in one direction and it is blowing on one side (plus), but it is suctioning on the other side (minus). When you turn the propeller from the right side, then it is turning in the contrary direction and the air current is in the opposite direction. But you cannot turn the propeller from above. Exactly the same picture we have with the magnet and the wire.