Magnetic poles of the same type attract and like poles repel. Types and types of magnets

Christmas Eve. The evening before Christmas. Fussy, but at the same time peaceful. An evening usually spent with family. An evening in which miracles are expected.

Sasha narrowed his eyes, wincing from the prickly snowflakes. In the light of the street lamps, the snow seemed much more magically silver than in the rays of the sun. If only he wouldn’t be so in your eyes... Myron pulled his scarf higher and pulled his hat down over his eyebrows. Quite cool, good thing there is no wind.

On this evening it is customary to be with family - Sasha knew this very well. But - alas - not today, definitely. Now that the anger has cooled down and the nerves have calmed down, misunderstanding has set in - how could one quarrel with everyone at once? At first, having quarreled to pieces in the Kaimanovs, Sasha wanted to go to his room, but at the door he ran into Thea. Excited, he made some kind of barb, thereby angering his girlfriend. And then Dan also fell under the hot hand. So what now? Sasha walks alone along the almost deserted streets, cursing himself for freaking out and leaving. And even on the evening before Christmas. It didn't turn out well.

“I’ll come back later, when everyone is asleep,” Myron decided to himself and, having cleared the snow from the bench, sat down on its edge.

And it kept snowing. Slow, easy. A typical windless winter evening. It would seem how Christmas Eve differs from others winter evenings? A year has already passed, and miracles have not happened. Unless there are various surprises, both pleasant and not.

Myron seemed to have woken up from a dream. Before he had time to come to his senses, someone’s cold small palms first touched his cheeks, and then thin arms wrapped around his neck.

Rakuri?!

Sasha rubbed his eyes and took a closer look. He simply couldn't believe his eyes. This is the same girl with whom he had a chance to walk in the fresh green park in the summer... And she hasn’t even changed! Cute round face, red-brown eyes, light, almost weightless body. Even the clothes are the same - a red dress and black sandals.

It's cold! - Sasha was indignant.

I'm not cold. “I’m used to it,” Rakuri shrugged.

I don't believe it...

Well, don't believe it. Why are you sitting here alone? Did you go to the store again?

Sasha laughed:

It's too late to go buy bread! I'm walking... Why are you here, and undressed too?!

I promised to return.

Myron looked at her carefully. And really, she promised. And she returned. But it felt like she knew exactly where to look for Sasha, and that he would be alone.

But I won’t feed you anymore, I don’t have any money with me,” Sasha smiled sadly, throwing up his hands.

And don't. - Rakuri put her hands on his broad shoulders. - You showed me your world, now I want to show you mine.

Rakuri took Myron by the hand and, taking steps back, made him stand up and follow her. Sasha hesitated a little, not knowing whether to do this, but still decided to go.

How do you not freeze? - Sasha asked, perplexed, following the girl.

When we come to my world, you yourself will understand,” Rakuri said with slight sadness. - I'll introduce you to someone else.

They walked further in silence. Sasha simply didn’t know what to start talking about. Rakuri's appearance was not just unexpected - it was stunning. He did not expect to meet her at all; it seemed to him that after the summer walk she would never appear again. But here it is - quite real, material. Only my hands are very cold. Although, is it any wonder it’s so cold outside? In the end, Sasha could not resist and wrapped his scarf around Rakuri's neck. She looked around in surprise, stopping.

It's cold for me to look at you. You’ll get sick on top of that,” Sasha grumbled.

I’m telling you seriously, I won’t get sick,” Rakuri smiled in response and moved on.

Myron shook his head and suddenly noticed that all the buildings had disappeared somewhere, and instead of them an unfamiliar icy void appeared, only snow was still slowly falling from the sky. There are only snowdrifts and bare trees around, and somewhere in the distance there are black rocks reaching into the sky. Sasha squeezed Rakuri's hand tighter, looking around worriedly.

What kind of place is this?!

“We are already in my world,” Rakuri said calmly. - Sorry, there is no cafe here like in your world, so I can’t treat you. As you should do when inviting someone to visit.

Rakuri slowly walked through the snow creaking under her feet, not letting go of Sasha’s hand. He tightly squeezed her miniature palm, and with his other hand he carefully grabbed her shoulders because it was quite difficult to go down these snowdrifts without falling. And so they walked for about half an hour until they reached the foot of the mountains. Myron squinted his eyes, trying to see what was there. He saw several caves, the entrances to which were hung with thick but tattered fabric. My heart began to beat restlessly - someone lives there, and not just one or two people. Although, do people live here?

Don't worry. As long as you are next to me, no one will touch you,” Rakuri said encouragingly and led Myron into one of the caves.

Who is this?! - Someone’s thick and menacing voice was immediately heard.

Sasha recoiled back from this unexpected exclamation. The first thing that caught his eye was a woman dressed in a dress with blond hair gathered in a ponytail and scarlet eyes, and on her shoulder was a scabbard with two-handed sword. Moreover, she turned out to be quite tall and muscular, which surprised Sasha, who was used to short people due to his two-meter height. She walked up to Myron and Rakuri with long strides and, bending down, gazed into the face of a man she did not know.

Valerie, stop it,” Rakuri said in a calm, even cold voice. - His name is Sasha. I brought him here.

This time its owner turned out to be a short, good-looking guy, although at first glance Sasha thought it was a girl. The guy was sitting on the floor and fiddling with his white and surprisingly long hair, on which a veil was secured with rose pins. He got up from the floor and came closer to get a better look at Sasha.

Isadel! - Valerie barked at the guy.

“Don’t yell at me,” he answered calmly.

While they were sorting things out among themselves, Myron looked around the cave, which he was unable to do right away. Suddenly it felt cozy here, albeit in its own way. Books, old kerosene stoves, shabby toys and some strange rubbish are scattered everywhere. And it looks like the cave has been built for a long time.

Never mind. I don’t bring guests often,” Rakuri said.

And then Sasha felt some movement from behind, so, turning around, he prepared to defend himself, but instead of the expected danger, a small, gentle, gray-eyed girl appeared in front of him, taller than Rakuri, but just as fragile and thin, with curly lavender hair, dressed in a dress by size. The girl blinked her eyes in surprise, not understanding who she saw in front of her.

Well... I’m Sasha,” Miron tried to introduce himself, but scared the girl a little with his chesty and hoarse voice.

Oh, redhead! - the girl giggled playfully. - I'm Loralei!

Get away from him! He is not from our world! - another voice rang out.

Sasha saw approaching a short but menacing woman dressed in a dress with sharp features and long hair below the waist. Already from afar it was visible how she sparkled with her evil yellow eyes. Approaching, the woman looked at Myron with a contemptuous look, and then, looking at Rakuri with irritation, disappeared into a nearby cave. Sasha didn’t even understand what the woman wanted to say.

This is Remilia. She’s always like this,” Rakuri explained. - This is where I live. With them. But you haven't seen everyone yet.

And don't! - Valerie snorted and, turning sharply, went further into the cave.

Sasha looked at Isadel and Loralei. The guy was fiddling with his hair and carefully examining Myron from head to toe with his intelligent, piercing gaze, and the girl smiled carefree. Everything was so chaotic, unnatural and strange that even his head began to spin, and Sasha leaned on Rakuri’s shoulder, as if this could save him from falling.

Went. “You’ve seen enough,” she said and led Sasha by the hand out of the cave.

Myron took a deep breath of fresh frosty air. He still couldn’t gather his thoughts and understand where he ended up. They walked quite far from the caves, and the heart continued to beat quickly. Sasha still couldn’t calm down.

“You know, I think I should confess to you,” Rakuri said slowly. - You will laugh, but I created this world.

Are you a goddess?

I'm a Diva. And everyone you saw is also a Diva. Yes... I am a goddess.

Sasha looked at the light, weightless figure of Rakuri and tried to understand how she could be the one who creates worlds. No, it doesn’t fit in my head at all. This girl cannot be the creator of worlds.

Don't you believe me? - asked Rakuri.

How can I just believe this? - Sasha threw up his hands. - Okay, you brought me into this world, introduced me to strange people... But I just can’t believe that you created all this... So aren’t you cold?

Not at all... Turn away.

Turn away.

Myron shrugged, but still turned away. And just a couple of seconds later someone's arms fell on his shoulders. big hands. Sasha almost jumped in surprise and turned around. Rakuri had disappeared somewhere, but instead of her stood an unusually tall woman, about three heads taller than Myron, with black, pitch-black hair. long hair. Only after looking closer did Sasha realize that this woman had the face of the little girl with whom he came into this world.

Rakuri?! - Myron exclaimed.

Yes, it’s me,” she tilted her head to the side. - Believe me, I'm not human.

You're so... tall...

You must be embarrassed.

Rakuri came closer. She was breathing loudly and irregularly, worried. Her palm, which had become wide, lay on Sasha’s shoulder, and the other Rakuri touched his red hair. Myron looked up at her and was silent. Slowly and hesitantly, he touched her hand to his shoulder.

“So cold...” flashed through Sasha’s head.

Everything is always icy here. We are all cold too. And they’re empty from the inside,” said Rakuri. - In fact, I’m not at all what you want me to be. You and I are like two poles - completely different.

Funny. Opposite poles attract,” Sasha smiled. - It can’t be that you’re empty inside. I don't think so.

You can think whatever you want, but you won’t change my essence.

Myron looked into her cold, calm eyes and smiled warmly. After changing her appearance, the scarf did not disappear from Rakuri's neck. Therefore, she did not seem cold and empty to Sasha. The scarf made her look more alive. More native.

You're a stupid little girl. How can you say that? Everyone can change. An empty glass can be filled with wonderful wine,” Sasha said affectionately.

Rakuri pulled away sharply and in an instant accepted her common appearance. Her face became sad and a little scared. Small drops of tears rolled from her scarlet-brown eyes. Sasha sat down next to him and extended his arms to hug him, but Rakuri pulled away, but this did not stop Myron from making another attempt and still embracing Rakuri in his arms. But she did not cry; the tears quickly dried on her cold face. Rakuri pressed Sasha's jacket onto his back with her small hands and buried her face in his shoulder. But she didn’t cry, didn’t even sob.

You are good, Sasha. But I'm no good. Neither bad nor good. “I’m just a Diva,” said Rakuri, pushing Myron away from him. - It's time for you to go home.

Really...

Sasha stood up abruptly and looked around. Literally a few meters away from him and Rakuri stood four people. Very tall people, hardly any of them reach Sasha’s shoulder. One of them - a white-haired guy - looks menacingly, an uncontrollable flame splashes in his red eyes. And how he isn’t cold in just his pants with suspenders is not clear. The tallest of them is a woman. Her face and hands are disfigured with scars, one eye is covered with a bandage, and the other - bluish-crystal - looks wary. Shaking a shock of unwashed dark hair, the woman wraps her cloak every now and then. Next to her is a fair-haired girl, also in a raincoat and pants, she looks more friendly than the other two.

The guy’s name is Dick, that woman with the scars is Rachel, and she’s Yoko,” she immediately listed all the Rakuri, getting up from the snow.

Who is this man? - Rachel asked.

Sasha,” they calmly answered her.

Is he a Diva?

Dick looked at Sasha very carefully, appraisingly, but quickly looked away. Myron can do no less menacing eyes. Yoko approached him and, looking intently into his eyes, smiled, thereby forcing Sasha to respond in kind.

It’s time for you to go home,” Rakuri reminded. - They'll take you through.

Yes, let us...! - Dick was about to shout, but he was interrupted.

I said: carry out!

Dick was forced to shut up, but, however, he still snorted angrily. Yoko extended her hand to Sasha, and Rachel just chuckled.

And you? - Sasha became worried.

And I stay at home. Hold the scarf...

Keep it for yourself.

Myron restrained himself so as not to cry. It became terribly sad. Why doesn’t she want to see him off, but trusts it to those whom Sasha sees for the first time?..

My children won't do anything to you. See you. - That was the last thing Sasha heard before Rakuri suddenly disappeared.

Went. “We’ll see you off,” Yoko said, smiling.

Myron had no choice but to follow them. The path along which he was led turned out to be completely different from the one he and Rakuri had followed to reach the rocks. Sasha trudged behind the trio, looking at their broad backs. Why did she call them her children? This is exactly what Myron asked them.

She created us. She created everything here,” Rachel said.

Because she's a Diva? - asked Sasha.

Because she is a goddess.

“So, after all, you are a goddess. I was not mistaken,” thought Sasha.

He was no longer surprised that Rachel, Yoko and Dick disappeared, and instead of the icy emptiness, buildings and roads appeared. Here too it's snowing. Prickly sparkling snow.

“Why didn’t you promise to return, fool? Although, no, she said “see you later,” Myron thought upset. “You’re not empty at all. You’re good.”

After standing for a minute in thought, Sasha went home. They were probably waiting for him there. After all, it’s Christmas, you need to be with your family.

Properties of permanent magnets. 1. Opposite magnetic poles attract, like magnetic poles repel. 2. Magnetic lines are closed lines. Outside the magnet magnetic lines leave “N” and enter “S”, closing inside the magnet. In 1600 English physician G.H. Gilbert deduced the basic properties of permanent magnets.

Slide 9 from the presentation "Permanent magnets, the Earth's magnetic field". The size of the archive with the presentation is 2149 KB.

Physics 8th grade

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Improved: 10.03.16

About magnets

Magnet - a body that has magnetization.

Field – this is the space within which one object (Source) influences, not necessarily by direct contact, another object (Receiver). If the Source of influence is a magnet, then the field is considered magnetic.

Magnetic field - this is the space around everyone from the poles of a magnet and for this reason it has no restrictions in all directions ! The center of each magnetic field is the corresponding pole of the magnet.

More than one Source can be present in a certain limited space at the same time. The intensity of these Sources will not necessarily be the same. Accordingly, there can also be more than one center.

The resulting field in this case will not be uniform. At each Receiver point of such a field, the intensity will correspond to the sum of the intensities of the magnetic fields generated by all centers.

In this case, the northern magnetic fields and the southern magnetic fields should be considered to be of different signs. For example, if at some point of the total field the intensity of the southern magnetic field located there coincides with the intensity of the northern magnetic field located here, then the total intensity at the discussed Receiver point from the interaction of both fields will be equal to zero.

Permanent magnet - a product capable of maintaining its magnetization after the external magnetic field is turned off.

Electromagnet - a device in which a magnetic field is created in a coil only when flowing through it electric current.

The general property of any magnet, regardless of the type of magnetic field (northern or southern) isattraction to materials containing iron (Fe ) . With bismuth, an ordinary magnet works on repulsion. Physics cannot explain either effect, although an unlimited number of hypotheses can be proposed ! Some grades of stainless steel, which also contain iron, are excluded from this rule (“attraction”) - physics also cannot explain this feature, although an unlimited number of hypotheses can also be proposed !

Magnetic pole - one of the sides of the magnet. If a magnet is suspended from middle part so that the poles have a vertical orientation and it (the magnet) can rotate freely in the horizontal plane, then one of the sides of the magnet will turn towards the north pole of the Earth. Accordingly, the opposite side will turn towards the south pole. The side of the magnet directed towards the north pole of the Earth is calledsouth pole magnet, and the opposite side -north pole magnet.

The magnet attracts other magnets and objects from magnetic materials without even being in contact with them. This action at a distance is explained by the existencemagnetic field in the space around both magnetic poles of a magnet.

Opposite poles of two magnets usually are attracted to each other , and the same names are usually mutualrepulse .

Why "usually"? Yes, because sometimes they meet anomalous phenomena, when, for example, opposite poles neither attract nor repel each other ! This phenomenon has a name "magnetic pit " Physics can't explain it !

In my experiments, I also encountered situations where like poles attract (instead of the expected mutual repulsion), and unlike poles repel (instead of the expected mutual attraction) ! This phenomenon doesn’t even have a name, and physics also can’t explain it yet. !

If a piece of non-magnetized iron is brought close to one of the poles of a magnet, the latter will become temporarily magnetized.

This material is considered magnetic.

In this case, the edge of the piece closest to the magnet will become a magnetic pole, the name of which is opposite to the name of the near pole of the magnet, and the far end of the piece will become a pole of the same name as the near pole of the magnet.

In this case, in the zone of mutual action there are two opposite poles of two magnets: the Source magnet and the conventional magnet (made of iron).

It was mentioned above that in the space between these magnets there is an algebraic addition of the intensities of the interacting fields. And, since the fields turn out to be of different signs, a zone of total magnetic field with zero (or almost zero) intensity is formed between the magnets. In what follows I will call such a zone “Zerozona ».

Since “Nature abhors a vacuum,” we can assume that she (Nature) seeks to fill the void with the nearest material “at hand.” In our case, such material is magnetic fields, between which a zero zone (Zerozone) has formed. To do this, it is necessary to bring both Sources of different signs closer together (bring the centers of magnetic fields closer together) until the zero zone between the fields completely disappears ! If, of course, nothing interferes with the movement of centers (bringing magnets closer together) !

Here is an explanation of the mutual attraction of opposite magnetic poles and the mutual attraction of a magnet with a piece of iron !

By analogy with attraction, we can consider the phenomenon of repulsion.

In this option, magnetic fields of the same sign appear in the zone of mutual influence. Of course, they also add together algebraically. Because of this, at the Receiver points between the magnets, a zone appears with an intensity higher than the intensities in neighboring areas. In what follows I will call such a zone “Maxisona ».

It is logical to assume that Nature strives to balance this nuisance and move the centers of interacting fields away from each other in order to smooth out the intensity of the field in Maxison.

With this explanation, it turns out that none of the poles of the magnet can move the piece of iron away from itself ! Because a piece of iron, being in a magnetic field, will always turn into a conditional temporary magnet and, therefore, magnetic poles will always form on it (on the piece of iron). Moreover, the near pole of the newly formed temporary magnet is opposite to the pole of the Source magnet. Consequently, a piece of iron located in the magnetic field of the Source pole will be attracted to the Source magnet (BUT not attract it ! )!

A conditional magnet, formed from a piece of iron placed in a magnetic field, behaves like a magnet only in relation to the Source magnet. But, if another piece of iron is placed next to this conditional magnet (piece of iron), then these two pieces of piece of iron will behave in relation to each other like ordinary two pieces of piece of iron ! In other words, the first magnet-piece of iron, as it were, forgets that it is a magnet ! It is only important that the thickness of the first piece of iron is sufficiently noticeable (for my home magnets - at least 2 mm) and the transverse dimension is larger than the size of the second piece of iron !

But the pole of the same name of a forcibly inserted magnet (this is no longer a simple piece of iron) will definitely move the same pole away from itself if there are no obstacles !

In physics textbooks, and sometimes in reputable works on physics, it is written that some idea of ​​​​the intensity of the magnetic field and the change in this intensity in space can be obtained by pouring iron filings onto a sheet of substrate (cardboard, plastic, plywood, glass or any non-magnetic material) placed on a magnet. The sawdust will line up in chains in the directions of varying field intensity, and the density of the sawdust lines will correspond to the very intensity of this field.

So this is cleandeception !!! It looks like it never occurred to anyone to conduct a real experiment and pour in this sawdust !

The sawdust will gather in two dense piles. One pile will form around the north pole of the magnet, and the other around it. south pole!

An interesting fact is that just in the middle between the two heaps (in Zerozon) in general NOT will no sawdust ! This experiment casts doubt on the existence of the notorious magneticpower lines , which must leave the north pole of the magnet and enter its south pole !

M. Faraday, to put it mildly, was wrong !

If there is a lot of sawdust, then as you move away from the pole of the magnet, the pile will decrease and thin out, which is an indicator of the weakening of the intensity of the magnetic field as the Receiver point moves away in space from the Source point on the pole of the magnet. The observed decrease in magnetic field intensity, of course, does not depend on the presence or absence of sawdust on the experimental substrate ! Reduction – objective !

But the decrease in the density of the sawdust coating on the substrate can be explained by the presence of friction of sawdust on the substrate (on cardboard, on glass, etc.). Friction prevents the weakened attraction from moving the sawdust towards the pole of the magnet. And the farther from the pole, the less strength attraction and, thus, the less sawdust will be able to approach the pole. But, if you shake the substrate, then ALL the sawdust will gather as close as possible to the nearest pole ! The visible non-uniform density of the sawdust coating will thus be leveled out !

In the middle zone of the cross sections of the magnet, two magnetic fields are added algebraically: northern and southern. The total field density between the poles is the result of the algebraic addition of intensities from opposite fields. In the very middle section, the sum of these intensities will be exactly zero (a Zerozone is formed). For this reason, in this section there should be no sawdust at all and they actually No!

As you move away from the middle of the magnet (from the Zerozone) towards the magnetic pole (any), the intensity of the magnetic field will increase, reaching a maximum at the pole itself. The gradient of change in the middle intensity is many times higher than the gradient of change in the outer intensity.

But, in any case, the sawdust will NEVER line up in at least the semblance of some lines connecting the north pole of the magnet with its south pole !

Physics operates with the term “Magnetic flux ».

So, there is NOT anymagnetic flux !

After all " flow " means "unidirectional movement of material particles or parts" ! If these particles are magnetic, then the flow is considered magnetic.

There are, of course, also figurative phrases such as “flow of words”, “stream of thoughts”, “stream of troubles” and similar phrases. But they have nothing to do with physical phenomena.

But in a real magnetic field, nothing moves anywhere ! There is only a magnetic field, the intensity of which decreases with distance from the nearest pole of the Source magnet.

If a flow existed, then a mass of particles would constantly flow out of the mass of the magnet ! And over time, the mass of the original magnet would noticeably decrease ! However, practice does not confirm this !

Since the existence of the notorious magnetic lines of force is not confirmed by practice, the term itself becomes far-fetched and invented.magnetic flux ».

Physics, by the way, gives such an interpretation of the magnetic flux, which only confirms the impossibility of “magnetic flux» in Nature:

« Magnetic flux"- physical quantity equal to the flux density of lines of force passing through an infinitesimal area dS ... (Continued interpretation can be viewed on the Internet).

Already from the beginning of the definition it follows nonsense ! « Flow", it turns out that this is the ordered movement of “lines of force” that do not exist in Nature ! Which in itself is already nonsense ! It is impossible from lines at all ( ! ) to form a “Flow”, since the line is NOT a material object (substance) ! And it is even more NOT possible to form a flow from non-existent lines !

What follows is an equally interesting message. ! It turns out that the totality of non-existent lines of force forms a certain “density”. According to the principle: the more lines that do not exist in Nature are collected in a limited section, the denser the non-existent bundle of non-existent lines becomes !

Finally, " Flow" - this, according to physicists, is a physical size!

What is called - " WE HAVE ARRIVED» !!!

I invite the Reader to figure it out for himself and understand why, say, “dream” cannot be a physical quantity?

Even if " Magnetic flux"existed, then in any case "Movement" (and "Flow" is "Movement") cannot exist size! "“Value” can be some movement parameter, for example: “Speed” of movement, “Acceleration” of movement, but not the “Movement” itself. !

Because simply the term "Magnetic flux“Physics couldn’t digest it, physicists had to supplement this term somewhat. Now physicists have it - “Magnetic induction flux "(although, due to illiteracy, it is often found simply "Magnetic flux») !

Radish horseradish, of course, is not sweeter !

« Induction » is not a material substance ! Therefore, it cannot form a thread ! « Induction" is just a foreign translation from the Russian term "Guidance», « Transition from private to general» !

You can use the term "Magnetic induction ", as the influence of a magnetic field, but the term "Magnetic induction flux» !

In physics there is a term "Magnetic flux density » !

But, thank God, it is difficult for physicists to define this concept ! And that’s why they (physicists) don’t give it !

And, if in physics a concept meaning nothing has taken root, such as “magnetic flux density", which for some reason is confused with the concept "magnetic induction", That:

Magnetic flux density (really NOT existing), it is more logical to count not the number of lines of force that do not exist in Nature per unit section perpendicular to any non-existent line of force, but attitude the number of sawdust found in a unit section of the magnetic field relative to the number of the same sawdust, taken as a unit, in the same unit section, but at the pole itself, if the sections under consideration are perpendicular tomagnetic field vector .

I suggest instead of the meaningless term "Magnetic flux density"to use a more logical term that defines the force with which the Source of the magnetic field can influence the Receiver - "Magnetic field intensity » !

This is something similar to “Electromagnetic field strength».

Of course, no one will ever measure these amounts of sawdust. ! Yes, no one will ever need this !

In physics the term "Magnetic induction » !

It is a vector quantity (i.e. “Magnetic induction" is a vector) and shows with what force and in what direction the magnetic field acts on a moving charge !

I immediately give a significant amendment to the interpretation accepted in physics !

Magnetic field NOT valid on charge! Regardless of whether this charge is moving or not !

The magnetic field of the Source interactswith magnetic field , generated moving charge !

It turns out that "magnetic induction" is nothing more than "strength", pushing a current-carrying conductor ! A "strength", pushing a conductor with current, is nothing more than "Magnetic induction» !

And in physics the following message is proposed: “The direction from the south pole is taken as the positive direction of the magnetic induction vector S to the north pole N magnetic needle freely positioned in a magnetic field.”

What if there is no compass needle nearby? ! While?

Then I suggest the following !

If the current-carrying conductor is located in the northern magnetic field zone, then the vector comes from closest to the conductor The source point is at the north pole of the magnet and intersects the conductor.

If the conductor with current is in the zone of the southern magnetic field, then the vector comes from the closest magnetic pole Receiver point on the conductor to the nearest Source point on the south pole of the magnet.

In other words, in any case, the shortest distance from the conductor to the nearest pole is taken. Further, depending on this distance, the magnitude of the force of the direct influence of the magnetic field on the conductor is taken (best of all - from an experimental graph of the dependence of magnetic force on distance).

I propose to perceive the shortest distance described as “Magnetic field vector ».

Thus, it turns out that an unlimited set of magnetic fields around one magnet (and, accordingly, the number of magnetic field vectors) can be isolated ! As many as you can build normals to the surfaces of the magnetic poles.

There are two magnets different types. Some are so-called permanent magnets, made from “hard magnetic” materials. Their magnetic properties are not associated with the use of external sources or currents. Another type includes the so-called electromagnets with a core made of “soft magnetic” iron. The magnetic fields they create are mainly due to the fact that an electric current passes through the winding wire surrounding the core.

Magnetic poles and magnetic field.

The magnetic properties of a bar magnet are most noticeable near its ends. If such a magnet is hung by the middle part so that it can rotate freely in a horizontal plane, then it will take a position approximately corresponding to the direction from north to south. The end of the rod pointing north is called the north pole, and the opposite end is called the south pole. Opposite poles of two magnets attract each other, and like poles repel each other.

If a bar of non-magnetized iron is brought close to one of the poles of a magnet, the latter will become temporarily magnetized. In this case, the pole of the magnetized bar closest to the pole of the magnet will be opposite in name, and the far one will have the same name. The attraction between the pole of the magnet and the opposite pole induced by it in the bar explains the action of the magnet. Some materials (such as steel) themselves become weak permanent magnets after being near a permanent magnet or electromagnet. A steel rod can be magnetized by simply passing the end of a permanent bar magnet along its end.

So, a magnet attracts other magnets and objects made of magnetic materials without being in contact with them. This action at a distance is explained by the existence of a magnetic field in the space around the magnet. Some idea of ​​the intensity and direction of this magnetic field can be obtained by pouring iron filings onto a sheet of cardboard or glass placed on a magnet. The sawdust will line up in chains in the direction of the field, and the density of the sawdust lines will correspond to the intensity of this field. (They are thickest at the ends of the magnet, where the intensity of the magnetic field is greatest.)

M. Faraday (1791–1867) introduced the concept of closed induction lines for magnets. The induction lines extend into the surrounding space from the magnet at its north pole, enter the magnet at its south pole, and pass inside the magnet material from the south pole back to the north, forming a closed loop. The total number of induction lines emerging from a magnet is called magnetic flux. Magnetic flux density, or magnetic induction ( IN), is equal to the number of induction lines passing along the normal through an elementary area of ​​unit size.

Magnetic induction determines the force with which a magnetic field acts on a current-carrying conductor located in it. If the conductor through which the current passes I, is located perpendicular to the induction lines, then according to Ampere’s law the force F, acting on the conductor, is perpendicular to both the field and the conductor and is proportional to the magnetic induction, current strength and length of the conductor. Thus, for magnetic induction B you can write an expression

Where F– force in newtons, I– current in amperes, l– length in meters. The unit of measurement for magnetic induction is tesla (T).

Galvanometer.

A galvanometer is a sensitive instrument for measuring weak currents. A galvanometer uses the torque produced by the interaction of a horseshoe-shaped permanent magnet with a small current-carrying coil (a weak electromagnet) suspended in the gap between the poles of the magnet. The torque, and therefore the deflection of the coil, is proportional to the current and the total magnetic induction in the air gap, so that the scale of the device is almost linear for small deflections of the coil.

Magnetizing force and magnetic field strength.

Next, we should introduce another quantity characterizing the magnetic effect of electric current. Suppose that current passes through the wire of a long coil, inside of which there is a magnetizable material. The magnetizing force is the product of the electric current in the coil and the number of its turns (this force is measured in amperes, since the number of turns is a dimensionless quantity). Magnetic field strength N equal to the magnetizing force per unit length of the coil. Thus, the value N measured in amperes per meter; it determines the magnetization acquired by the material inside the coil.

In a vacuum magnetic induction B proportional to the magnetic field strength N:

Where m 0 – so-called magnetic constant having a universal value of 4 p H 10 –7 H/m. In many materials the value B approximately proportional N. However, in ferromagnetic materials the ratio between B And N somewhat more complicated (as will be discussed below).

In Fig. 1 shows a simple electromagnet designed to grip loads. The energy source is a DC battery. The figure also shows the field lines of the electromagnet, which can be detected by the usual method of iron filings.

Large electromagnets with iron cores and very a large number ampere-turns operating in continuous mode have a large magnetizing force. They create a magnetic induction of up to 6 Tesla in the gap between the poles; this induction is limited only by mechanical stress, heating of the coils and magnetic saturation of the core. A number of giant water-cooled electromagnets (without a core), as well as installations for creating pulsed magnetic fields, were designed by P.L. Kapitsa (1894–1984) in Cambridge and at the Institute of Physical Problems of the USSR Academy of Sciences and F. Bitter (1902–1967) in Massachusetts Institute of Technology. With such magnets it was possible to achieve induction of up to 50 Tesla. A relatively small electromagnet that creates fields up to 6.2 Tesla, consuming electrical power 15 kW and cooled by liquid hydrogen, was developed at the Losalamos National Laboratory. Similar fields are obtained at cryogenic temperatures.

Magnetic permeability and its role in magnetism.

Magnetic permeability m is a quantity characterizing the magnetic properties of a material. Ferromagnetic metals Fe, Ni, Co and their alloys have very high maximum permeabilities - from 5000 (for Fe) to 800,000 (for supermalloy). In such materials at relatively low field strengths H large inductions occur B, but the relationship between these quantities is, generally speaking, nonlinear due to the phenomena of saturation and hysteresis, which are discussed below. Ferromagnetic materials are strongly attracted by magnets. They lose their magnetic properties at temperatures above the Curie point (770° C for Fe, 358° C for Ni, 1120° C for Co) and behave like paramagnets, for which induction B up to very high tension values H is proportional to it - exactly the same as it is in a vacuum. Many elements and compounds are paramagnetic at all temperatures. Paramagnetic substances are characterized by the fact that they become magnetized in an external magnetic field; if this field is turned off, the paramagnetic substances return to a non-magnetized state. Magnetization in ferromagnets is maintained even after the external field is turned off.

In Fig. Figure 2 shows a typical hysteresis loop for a magnetically solid (with big losses) ferromagnetic material. It characterizes the ambiguous dependence of the magnetization of a magnetically ordered material on the strength of the magnetizing field. With increasing magnetic field strength from the initial (zero) point ( 1 ) magnetization occurs along the dashed line 1 –2 , and the value m changes significantly as the magnetization of the sample increases. At the point 2 saturation is achieved, i.e. with a further increase in voltage, the magnetization no longer increases. If we now gradually decrease the value H to zero, then the curve B(H) no longer follows the same path, but passes through the point 3 , revealing, as it were, a “memory” of material about “ past history", hence the name "hysteresis". It is obvious that in this case some residual magnetization is retained (segment 1 –3 ). After changing the direction of the magnetizing field to the opposite direction, the curve IN (N) passes the point 4 , and the segment ( 1 )–(4 ) corresponds to the coercive force that prevents demagnetization. Further increase in values ​​(- H) brings the hysteresis curve to the third quadrant - the section 4 –5 . The subsequent decrease in value (- H) to zero and then increasing positive values H will lead to the closure of the hysteresis loop through the points 6 , 7 And 2 .

Hard magnetic materials are characterized by a wide hysteresis loop, covering a significant area on the diagram and therefore corresponding to large values ​​of remanent magnetization (magnetic induction) and coercive force. A narrow hysteresis loop (Fig. 3) is characteristic of soft magnetic materials, such as mild steel and special alloys with high magnetic permeability. Such alloys were created with the aim of reducing energy losses caused by hysteresis. Most of these special alloys, like ferrites, have high electrical resistance, which reduces not only magnetic losses, but also electrical losses caused by eddy currents.

Magnetic materials with high permeability are produced by annealing, carried out by holding at a temperature of about 1000 ° C, followed by tempering (gradual cooling) to room temperature. In this case, preliminary mechanical and thermal treatment, as well as the absence of impurities in the sample, are very important. For transformer cores at the beginning of the 20th century. silicon steels were developed, the value m which increased with increasing silicon content. Between 1915 and 1920, permalloys (alloys of Ni and Fe) appeared with a characteristic narrow and almost rectangular hysteresis loop. Especially high values magnetic permeability m at small values H the alloys differ in hypernic (50% Ni, 50% Fe) and mu-metal (75% Ni, 18% Fe, 5% Cu, 2% Cr), while in perminvar (45% Ni, 30% Fe, 25% Co ) value m practically constant over a wide range of changes in field strength. Among modern magnetic materials, mention should be made of supermalloy, an alloy with the highest magnetic permeability (it contains 79% Ni, 15% Fe and 5% Mo).

Theories of magnetism.

For the first time, the guess that magnetic phenomena are ultimately reduced to electrical phenomena arose from Ampere in 1825, when he expressed the idea of ​​​​closed internal microcurrents circulating in each atom of a magnet. However, without any experimental confirmation of the presence of such currents in matter (the electron was discovered by J. Thomson only in 1897, and the description of the structure of the atom was given by Rutherford and Bohr in 1913), this theory “faded.” In 1852, W. Weber suggested that each atom of a magnetic substance is a tiny magnet, or magnetic dipole, so that complete magnetization of a substance is achieved when all individual atomic magnets are aligned in a certain order (Fig. 4, b). Weber believed that molecular or atomic “friction” helps these elementary magnets maintain their order despite the disturbing influence of thermal vibrations. His theory was able to explain the magnetization of bodies upon contact with a magnet, as well as their demagnetization upon impact or heating; finally, the “reproduction” of magnets when cutting a magnetized needle or magnetic rod into pieces was also explained. And yet this theory did not explain either the origin of the elementary magnets themselves, or the phenomena of saturation and hysteresis. Weber's theory was improved in 1890 by J. Ewing, who replaced his hypothesis of atomic friction with the idea of ​​interatomic confining forces that help maintain the ordering of the elementary dipoles that make up a permanent magnet.

The approach to the problem, once proposed by Ampere, received a second life in 1905, when P. Langevin explained the behavior of paramagnetic materials by attributing to each atom an internal uncompensated electron current. According to Langevin, it is these currents that form tiny magnets, randomly oriented when external field absent, but acquiring an ordered orientation after its application. In this case, the approach to complete order corresponds to saturation of magnetization. In addition, Langevin introduced the concept of a magnetic moment, which for an individual atomic magnet is equal to the product of the “magnetic charge” of a pole and the distance between the poles. Thus, the weak magnetism of paramagnetic materials is due to the total magnetic moment created by uncompensated electron currents.

In 1907, P. Weiss introduced the concept of “domain,” which became an important contribution to the modern theory of magnetism. Weiss imagined domains as small “colonies” of atoms, within which the magnetic moments of all atoms, for some reason, are forced to maintain the same orientation, so that each domain is magnetized to saturation. An individual domain can have linear dimensions of the order of 0.01 mm and, accordingly, a volume of the order of 10–6 mm 3. The domains are separated by so-called Bloch walls, the thickness of which does not exceed 1000 atomic sizes. The “wall” and two oppositely oriented domains are shown schematically in Fig. 5. Such walls represent “transition layers” in which the direction of domain magnetization changes.

In the general case, three sections can be distinguished on the initial magnetization curve (Fig. 6). In the initial section, the wall, under the influence of an external field, moves through the thickness of the substance until it encounters a defect in the crystal lattice, which stops it. By increasing the field strength, you can force the wall to move further, through the middle section between the dashed lines. If after this the field strength is again reduced to zero, then the walls will no longer return to their original position, so the sample will remain partially magnetized. This explains the hysteresis of the magnet. At the final section of the curve, the process ends with the saturation of the magnetization of the sample due to the ordering of the magnetization inside the last disordered domains. This process is almost completely reversible. Magnetic hardness is exhibited by those materials that have atomic lattice contains many defects that impede the movement of interdomain walls. This can be achieved mechanically and heat treatment, for example by compressing and then sintering the powdered material. In alnico alloys and their analogues, the same result is achieved by fusing metals into a complex structure.

In addition to paramagnetic and ferromagnetic materials, there are materials with so-called antiferromagnetic and ferrimagnetic properties. The difference between these types of magnetism is explained in Fig. 7. Based on the concept of domains, paramagnetism can be considered as a phenomenon caused by the presence in the material of small groups of magnetic dipoles, in which individual dipoles interact very weakly with each other (or do not interact at all) and therefore, in the absence of an external field, take only random orientations ( Fig. 7, A). In ferromagnetic materials, within each domain there is a strong interaction between individual dipoles, leading to their ordered parallel alignment (Fig. 7, b). In antiferromagnetic materials, on the contrary, the interaction between individual dipoles leads to their antiparallel ordered alignment, so that the total magnetic moment of each domain is zero (Fig. 7, V). Finally, in ferrimagnetic materials (for example, ferrites) there is both parallel and antiparallel ordering (Fig. 7, G), resulting in weak magnetism.

There are two convincing experimental confirmations of the existence of domains. The first of them is the so-called Barkhausen effect, the second is the method of powder figures. In 1919, G. Barkhausen established that when an external field is applied to a sample of ferromagnetic material, its magnetization changes in small discrete portions. From the point of view of domain theory, this is nothing more than an abrupt advance of the interdomain wall, encountering on its way individual defects that delay it. This effect is usually detected using a coil in which a ferromagnetic rod or wire is placed. If you alternately bring a strong magnet towards and away from the sample, the sample will be magnetized and remagnetized. Abrupt changes in the magnetization of the sample change the magnetic flux through the coil, and an induction current is excited in it. The voltage generated in the coil is amplified and fed to the input of a pair of acoustic headphones. Clicks heard through headphones indicate an abrupt change in magnetization.

To identify the domain structure of a magnet using the powder figure method, a drop of a colloidal suspension of ferromagnetic powder (usually Fe 3 O 4) is applied to a well-polished surface of a magnetized material. Powder particles settle mainly in places of maximum inhomogeneity of the magnetic field - at the boundaries of domains. This structure can be studied under a microscope. A method based on the passage of polarized light through a transparent ferromagnetic material has also been proposed.

Weiss's original theory of magnetism in its main features has retained its significance to this day, having, however, received an updated interpretation based on the idea of ​​uncompensated electron spins as a factor determining atomic magnetism. The hypothesis about the existence of an electron’s own momentum was put forward in 1926 by S. Goudsmit and J. Uhlenbeck, and at present it is electrons as spin carriers that are considered “elementary magnets”.

To explain this concept, consider (Fig. 8) a free atom of iron, a typical ferromagnetic material. Its two shells ( K And L), those closest to the nucleus are filled with electrons, with the first of them containing two and the second containing eight electrons. IN K-shell, the spin of one of the electrons is positive, and the other is negative. IN L-shell (more precisely, in its two subshells), four of the eight electrons have positive spins, and the other four have negative spins. In both cases, the spins of the electrons within one shell are completely compensated, so that the total magnetic moment is zero. IN M-shell, the situation is different, since out of the six electrons located in the third subshell, five electrons have spins directed in one direction, and only the sixth in the other. As a result, four uncompensated spins remain, which determines the magnetic properties of the iron atom. (In the external N-shell has only two valence electrons, which do not contribute to the magnetism of the iron atom.) The magnetism of other ferromagnets, such as nickel and cobalt, is explained in a similar way. Since neighboring atoms in an iron sample strongly interact with each other, and their electrons are partially collectivized, this explanation should be considered only as a visual, but very simplified diagram of the real situation.

The theory of atomic magnetism, based on taking into account the electron spin, is supported by two interesting gyromagnetic experiments, one of which was carried out by A. Einstein and W. de Haas, and the other by S. Barnett. In the first of these experiments, a cylinder of ferromagnetic material was suspended as shown in Fig. 9. If current is passed through the winding wire, the cylinder rotates around its axis. When the direction of the current (and therefore the magnetic field) changes, it turns in the opposite direction. In both cases, the rotation of the cylinder is due to the ordering of the electron spins. In Barnett's experiment, on the contrary, a suspended cylinder, sharply brought into a state of rotation, becomes magnetized in the absence of a magnetic field. This effect is explained by the fact that when the magnet rotates, a gyroscopic moment is created, which tends to rotate the spin moments in the direction of its own axis of rotation.

For a more complete explanation of the nature and origin of short-range forces that order neighboring atomic magnets and counteract the disordering influence of thermal motion, one should turn to quantum mechanics. A quantum mechanical explanation of the nature of these forces was proposed in 1928 by W. Heisenberg, who postulated the existence of exchange interactions between neighboring atoms. Later, G. Bethe and J. Slater showed that exchange forces increase significantly with decreasing distance between atoms, but upon reaching a certain minimum interatomic distance they drop to zero.

MAGNETIC PROPERTIES OF SUBSTANCE

One of the first extensive and systematic studies of the magnetic properties of matter was undertaken by P. Curie. He established that, according to their magnetic properties, all substances can be divided into three classes. The first category includes substances with pronounced magnetic properties, similar to the properties of iron. Such substances are called ferromagnetic; their magnetic field is noticeable at considerable distances ( cm. higher). The second class includes substances called paramagnetic; Their magnetic properties are generally similar to those of ferromagnetic materials, but much weaker. For example, the force of attraction to the poles of a powerful electromagnet can tear an iron hammer out of your hands, and to detect the attraction of a paramagnetic substance to the same magnet, you usually need very sensitive analytical balances. The last, third class includes the so-called diamagnetic substances. They are repelled by an electromagnet, i.e. the force acting on diamagnetic materials is directed opposite to that acting on ferro- and paramagnetic materials.

Measurement of magnetic properties.

When studying magnetic properties, two types of measurements are most important. The first of them is measuring the force acting on a sample near a magnet; This is how the magnetization of the sample is determined. The second includes measurements of “resonant” frequencies associated with the magnetization of matter. Atoms are tiny "gyros" and in a magnetic field precess (like a regular top under the influence of the torque created by gravity) at a frequency that can be measured. In addition, a force acts on free charged particles moving at right angles to the lines of magnetic induction, as does the electron current in a conductor. It causes the particle to move in a circular orbit, the radius of which is given by

R = mv/eB,

Where m– particle mass, v– its speed, e is its charge, and B– magnetic field induction. The frequency of such a circular motion is

Where f measured in hertz, e– in pendants, m– in kilograms, B- in Tesla. This frequency characterizes the movement of charged particles in a substance located in a magnetic field. Both types of motions (precession and motion along circular orbits) can be excited by alternating fields with resonant frequencies equal to the “natural” frequencies characteristic of of this material. In the first case, the resonance is called magnetic, and in the second - cyclotron (due to its similarity with the cyclic motion of a subatomic particle in a cyclotron).

Speaking about the magnetic properties of atoms, it is necessary to pay special attention to their angular momentum. The magnetic field acts on the rotating atomic dipole, tending to rotate it and place it parallel to the field. Instead, the atom begins to precess around the direction of the field (Fig. 10) with a frequency depending on the dipole moment and the strength of the applied field.

Atomic precession is not directly observable because all atoms in a sample precess at a different phase. If we apply a small alternating field directed perpendicular to the constant ordering field, then a certain phase relationship is established between the precessing atoms and their total magnetic moment begins to precess with a frequency equal to the precession frequency of individual magnetic moments. The angular velocity of precession is important. As a rule, this value is of the order of 10 10 Hz/T for magnetization associated with electrons, and of the order of 10 7 Hz/T for magnetization associated with positive charges in the nuclei of atoms.

A schematic diagram of a setup for observing nuclear magnetic resonance (NMR) is shown in Fig. 11. The substance being studied is introduced into a uniform constant field between the poles. If a radiofrequency field is then excited using a small coil surrounding the test tube, a resonance can be achieved at a specific frequency equal to the precession frequency of all nuclear “gyros” in the sample. The measurements are similar to tuning a radio receiver to the frequency of a specific station.

Magnetic resonance methods make it possible to study not only the magnetic properties of specific atoms and nuclei, but also the properties of their environment. The fact is that magnetic fields in solids and molecules are inhomogeneous, since they are distorted by atomic charges, and the details of the experimental resonance curve are determined by the local field in the region where the precessing nucleus is located. This makes it possible to study the structural features of a particular sample using resonance methods.

Calculation of magnetic properties.

The magnetic induction of the Earth's field is 0.5 x 10 –4 T, while the field between the poles of a strong electromagnet is about 2 T or more.

The magnetic field created by any configuration of currents can be calculated using the Biot-Savart-Laplace formula for magnetic field induction, created by the element current. Calculating the field created by circuits of different shapes and cylindrical coils is in many cases very complex. Below are formulas for a number of simple cases. Magnetic induction (in teslas) of the field created by a long straight wire carrying current I

The field of a magnetized iron rod is similar to the external field of a long solenoid, with the number of ampere-turns per unit length corresponding to the current in the atoms on the surface of the magnetized rod, since the currents inside the rod cancel each other (Fig. 12). By the name of Ampere, such a surface current is called Ampere. Magnetic field strength H a, created by the Ampere current, is equal to the magnetic moment per unit volume of the rod M.

If an iron rod is inserted into the solenoid, then in addition to the fact that the solenoid current creates a magnetic field H, the ordering of atomic dipoles in the magnetized rod material creates magnetization M. In this case, the total magnetic flux is determined by the sum of the real and Ampere currents, so that B = m 0(H + H a), or B = m 0(H+M). Attitude M/H called magnetic susceptibility and is denoted by the Greek letter c; c– dimensionless quantity characterizing the ability of a material to be magnetized in a magnetic field.

Magnitude B/H, which characterizes the magnetic properties of a material, is called magnetic permeability and is denoted by m a, and m a = m 0m, Where m a- absolute, and m– relative permeability,

In ferromagnetic substances the quantity c may have very large values– up to 10 4 е 10 6 . Magnitude c Paramagnetic materials have a little more than zero, and diamagnetic materials have a little less. Only in a vacuum and very weak fields quantities c And m are constant and independent of the external field. Induction dependence B from H is usually nonlinear, and its graphs, the so-called. magnetization curves, for different materials and even at different temperatures can differ significantly (examples of such curves are shown in Fig. 2 and 3).

The magnetic properties of matter are very complex, and their deep understanding requires a careful analysis of the structure of atoms, their interactions in molecules, their collisions in gases and their mutual influence in solids and liquids; The magnetic properties of liquids are still the least studied.

Opposite poles

I walked around a huge supermarket, throwing into the cart the first thing that came to hand. I tried not to think about what these knives, carpet cleaner and cheap watch with shiny rhinestones were for. The selection of goods should be as random as possible. As does the choice of cash register at the end of the trading floor.
The girl-cashier smiled affably with a duty smile, inquired by rote about the number of required packages and began to take barcode readings with clear movements of the robotic arm. The scanner worked flawlessly. The packages were not torn. And the goods did not even fall from the conveyor belt. But there was still hope when, with fingers trembling with excitement, I entered the bank card PIN code into the keyboard... Well!!! No. Everything is fine. "Your check." And still the same radiant smile.

I left the Porsche far from the entrance. In the very corner of the parking lot. The supermarket employee following on my heels was shaking my aching nerves more than the cold wind. “I wonder if I really look like the type of person who steals carts?” While this thought made me smile, it still worried me. I wanted to shout: “You can’t wait!” But I only increased my pace, trying to escape from my annoying pursuer.

The Porsche stood out as a proudly bright spot among the gray automobile iron standing next to it. He knew his worth and knew how to tell everyone around him about it. For those who will never get into such a car. Those who will never experience the power of its engine will never feel the warm luxury of the leather interior. She's too expensive for them. Just like for me now.

I was sitting behind the wheel, but did not move, waiting the allotted ten minutes. Now there was no need for this. The experiment with the store, and the clean roof of the sports car, deliberately left under the crow's nests, confirmed my worst suspicions. I became the same as everyone else. I give up... But habit is second nature. It will be difficult to get rid of her. Very difficult.
First you have to sell the car. Then - an apartment in a high-rise building. After…. Only after many years will everything that happened to me be forgotten so much that it will seem like a fairy tale. A strange invention that you can’t even talk about - they will laugh at you. And only a tattered diary will remind me that it still happened.

February 12, 1996.
I didn’t write for a long time because I couldn’t - I’m not left-handed after all. And my cast was removed only yesterday. Nothing special happened this month. Except that I almost got fired. But everything is in order. On the morning of January 5th, I was in a hurry to go to work, and got up before the janitor. It was so slippery that I fell right next to the entrance. I was lucky: I only hit my arm, and the ambulance arrived just an hour later. At the emergency room, a nurse I knew let me in out of turn. And the doctor was there and not even drunk. However, the X-ray film turned out to be defective. So they took the picture only the third time. Displaced fracture. It's good that it's closed.
While I was on sick leave, our laboratory was downsized. They didn’t completely liquidate it only because the director is a relative of Ivan Petrovich (well, yes, that same one). Only him and Professor Nikolaev were left. The old man was needed for scientific appearance and the appearance of useful work. The rest were sent to other departments for which there were no instructions from above. Well, they were going to fire me. As absent and extreme.
Is there anything else I can break?

February 19, 1996
The first day of work after sick leave went well. The laboratory director sent himself on vacation. So no one will fire me for another month. And the professor and I won’t be disturbed from playing checkers and talking about life. The old man is a good and interesting person. Eh, if only the boss had taken longer to treat his nerves at the dispensary!

February 26, 1996
On the way to work, climbing over a dirty snowdrift left by road workers at the sidewalk, I tripped, fell and broke my glasses. Fortunately, nothing else was damaged. But the most annoying thing is that about five minutes later this snowdrift was swallowed up by a snowblower!
The professor, not at all surprised by my shabby appearance, poured me a glass of port and began to listen with interest and sympathy about my next adventure. This is how it happened in our laboratory - I fall, and he listens.

February 29, 1996
Today the old man greeted me slightly excited. He waited with visible impatience for me to undress and sit down at my desk. All this time he walked around the laboratory, putting his hands behind his back and nervously twitching his head in time with his steps. He seemed to be echoing himself: “Yes, yes! That’s right!” I was intrigued. It was not often that I saw the professor in such tension. It was too much even for him. Finally, he couldn’t stand it: “Yes, listen, you, after all!”

The next half hour completely flew out of the fabric of the familiar and normal. It turned out that the professor had been writing down what he thought was the most important of my daily stories for many months. Systematized, with nothing to do. I analyzed it in order to shake off the moss from the old convolutions. I was looking for logic. And then yesterday it dawned on him. Probably the pressure outside was changing. He was not too lazy to stay in the laboratory overnight so that he could draw diagrams of my life on a graph plotter (so that’s what they are for, it turns out, these boxes are heavy!)!
Apparently, notes of distrust were too clearly audible in the words with which I assessed this titanic work, because the professor every now and then began to shout, beat his chest with his fist and added: “Yes, I’ll fail if I’m wrong!”
Finally, he grabbed a heavy horseshoe magnet and raised it above his head threateningly: “Look and listen carefully!” This argument seemed convincing to me, and I shut up. The professor raised a second magnet above his head, this time a bar magnet, and brought the two together. visual aids opposite poles. They naturally stuck to each other. But I thought it unsafe to applaud this successful experience. The old man, with difficulty pushing the magnets apart, explained: “This is you!” he put a horseshoe under my nose. “And this is trouble!” - He showed me another magnet. “You are attracted!” This truth did not please me, but it did not surprise me either. I myself have long suspected this. Without diagrams and even without magnets: “Is that all? Maybe then we’d better play checkers?”
But the old man was adamant: “Look further!” He repeated the same experiment, only this time, moving the flat magnet relative to the horseshoe-shaped one by ten centimeters. Now they touched only with their blue poles and, naturally, repelled. The professor invited me to see this for myself, and I was afraid to refuse. But I still didn’t understand the point.

And everything turned out to be very simple. When Nikolaev was finally able to descend to earth from the heaven of his genius, he easily and clearly explained to me the essence of this strange theory. In his opinion, I was a unique person. The troubles that beset me with enviable regularity were tied to me at certain time intervals. To avoid them, you just need to move your life back a little. About ten minutes, judging by his calculations. Or, to put it even more simply, as soon as you are about to do something, stop, wait the allotted minutes, and - go ahead! The trouble is already behind us!
For all the madness of this assumption, there was something in it. And I decided to try.

March 6, 1996
Everything is fine again. During these days I have not broken a single cup. I have never been hit with mud by a passing car. The neighbor's poodle even stopped barking at me!

March 12, 1996
The method works. Now I'm sure of this. And the proof is my misfortunes. They haven't gone anywhere. They still happen. But not with me. They walk ahead of me by the required ten minutes and happen to someone else. To those who find themselves in the place where I should be.

March 19, 1996
I brought the professor a box of his favorite port wine. I spent my last stash. The refrigerator is empty, and payday is still a week away. But I couldn’t do otherwise: today I was supposed to be hit by a car.

March 26, 1996
What happened this week is difficult to describe in a nutshell. But I will try to state the main thing: luck has taken the place of troubles in my life! I noticed this before, from the very beginning of the experiment. But he was afraid to frighten or jinx him, having admitted it to himself. But after my second birth, I believed so much in the professor’s genius that I went even further in testing his theory. I started playing. Little things: lotteries, slot machines. I won a little. But then - always!
And yesterday I went to the casino. And even though I don’t really know how to play roulette, I always knew what to bet on. After an hour of playing, when the stakes had already become indecently high, I realized from the looks of the guards that it would be difficult to leave. But I wasn't scared at all. I slowly cashed out my winnings. I waited ten minutes and went to the exit. The security had no time for me at that moment: they were working together to extinguish the electrical wiring that had shorted out in the cash register.

April 12, 1996
They finally signed my resignation letter. Now I don’t have to go to the other end of the city every day to this stupid laboratory.

April 27, 1997
I bought an apartment in a high-rise after a week-long trip to Montecarlo. Well, of course, I left a little for living, so as not to wander around the cheap Moscow gambling establishments. Thank God we have a free country. And no one yet asks how much money you live on.

September 8, 1998
I don’t understand those who suffered from the default. What kind of idiots you have to be to not have time to convert rubles into foreign currency!

March 18, 2000
They put it... How can I wash it now? You'll have to keep an eye on the servants so they don't saw off a piece!

*****************

November 6, 2008
And why did I buy Gazprom shares for 300 rubles in the summer, and on margin too?! Yes, and where did that damn professor go?!

December 12, 2008
Banks demand repayment of loans. They threaten with court and bailiffs. But there is no professor! He started this experiment and left me alone! Escaped! He's dead, he's an infection!!! And I had so much hope for him...

January 12, 2009
Today I will do what I want, trying not to wait the allotted 10 minutes. I still have hope that I have not become the same as everyone else. That my bad luck is still with me.
Let the dishes break, clothes tear and tires burst! I'll be looking forward to it. If only it turned out that the aim was just off. The interval between “+” and “-” has changed. And if so, I will find my fortune. No matter how much time and effort it takes me.

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Finally, the Porsche left the parking lot. The security guard, who had been standing nearby almost at attention all this time, came to life and wheeled the cart to the glass doors of the supermarket. And he managed just in time to catch the silent scene, the participants of which were sellers, cashiers, customers and an old woman who won a hundred thousand rubles as the millionth visitor to the store.