Electromagnetic fields - material from physics. Electromagnetic field
Short summary 8th grade
Heat boxes
Body temperature lies in the fluidity of the molecules.
The spineless roar of molecules is called thermal rukh.
Inner energy– this is the sum of the potential and kinetic energy of all the molecules that make up speech.
Inner energy don't lie low View of the khutra. ruin of the body in its position compared to other bodies.
As time progresses, t˚ increases.
Changes 2 ways:
1. Shlyakhom Vikonannya roboti;
2. The way to heat exchange (heat transfer)
Heat transfer:
1. Thermal conductivity– transfer of E from one part of the body to another through the thermal flow of molecules (solid body)
2. Convection– displacement of the speech itself in rivers and gases. (Ridina and gas)
3. Viprominyuvannya– preference for changes (no medium required, possible in a vacuum)
The intensity of warmth– energy that is removed or given in by the body during heat transfer.
Processes:
I. Heating or cooling (without changing the aggregate mill)
m – masa
Temperature change
c – the amount of heat capacity, numerically equal to the amount of heat that must be given to the skin kg of this substance in order to move it up by 1C.
II. Zgorannya paliva
m – masa
q – heat of burning fire - a physical quantity that shows how much heat is seen when burning fire weighing 1 kg.
3. Steam creation (vivapor, boiling water)
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5. Desublimation
6. Sublimation (likhtarstvo)
III. Melting and crystallization
the process of melting or crystallization occurs on the horizontal extension of the AB graph at a constant temperature, which is called melting temperature(Tabular value)
This is a schedule of performances on the ice melting process.
Krapka A - no ice
Intermediate AB – ice and water
Krapka B – just water
Melting – Q supplied to the system
Crystallization – Q is introduced into the system
m – masa
λ – pita heat melting shows how much heat must be transferred to the skin kg of speech taken at the melting temperature in order to melt its surface.
IV. Steam creation and condensation
The process of steam generation or condensation occurs on the horizontal extension of the AB graph at a constant temperature, which is called boiling temperature.(Tabular value)
This schedule of presentations is based on boiling water.
Point A – no water
Dilyanka AB – water and steam
Krapka B – no steam
Steam creation – Q supplied to the system
Condensation – Q is introduced into the system
m – masa
L – pita heat of steam creation shows how much heat must be applied to each kg of radish taken at boiling temperature in order to steam the radish.
Rape of couples- couples who are in a dynamic relationship with their homeland. (How many molecules go from one pair to another, how many molecules go back, from pair to one.)
ü Absolute humidity of the wind- The strength of water vapor in the wind.
ü Vidnosna vologisti wind- Ratio of absolute moisture to the intensity of infused steam at the same temperature.
Dew point is the temperature at which steam becomes saturated.
A hygrometer and a psychrometer are devices for air conditioning.
Thermal motors i – these are machines that convert internal energy into mechanical energy.
KKD - installation of a thorough engine operation, up to the energy removed from heating.
Electrical boxes
Electrostatics is the division that charges and rests.
Electrified bodies either attract or move.
The physical quantity that characterizes the stage of electrification of the body is called electric charge.
Methods of electrification:
1) Dotik (rubbing)
2) Torkannya
3) Through inflow
Mentally respect that the stick is cursed, rubbed on the seam - it’s charging positive, and the ebonite stick, rubbed on wool - negative.
Simultaneously charged bodies are drawn together, and differently charged bodies are attracted.
Around a charged body (or an indestructible charge) it sleeps electric field. When the fields interact, they vibrate Coulomb forces.
I – charge in C
– stand between the charges
k- Coefficient
Rozrakhunok sili pendant mozlivy three times:
1. Interaction of two charged spheres (r – from center to center)
2. Interaction between a charged sphere and a point charge (charged body, the dimensions of which can be customized)
3. Interaction of two point charges
An electroscope is a device for measuring an electric charge.
Electric strum– straightening and rearranging the charging of the particles. (in metals - rokh elektroniv)
All speeches with conductivity ate. struma is divided into 3 groups:
1) Guides(metals, rozchini - to take revenge on the greatest minds, to get richly charged particles)
2) Newswires- Speeches that place the free charge of particles with the smallest world (germanium, silicon)
3) Dielectrics (non-conductors)– do not contain freely charged particles – gum, ebonite, distiller. water.
Isolator- Body, made from dielectric.
An electron is the part with the least negative charge.
Center – nucleus (massive and positive): protons (+) and neutrons (0)
Next to the nucleus are electrons (light and negative)
Normal camp - neutral atom– for protons = for electrons
A positive ion is an atom that has lost one or more electrons
Negative ion - an atom that has acquired a real electron
Umovi viniknennya electric struma:
1) conductor
2) presence of an electric field
3) dzherelo struma - a device in which a field of charges is generated
4) 
closed electric lancet
Ate. the lance is formed:
ü dzherela struma
ü living companions
ü underwater wires
ü new adaptations
Ammeter- this is an adapter for vimiryuvanniya sil struma in lanzyuzi; turns on consistently!
Voltmeter- this is a device for adjusting the voltage in the country or in other areas; turns on in parallel!
Strumu power– a physical quantity, which is determined by the quantity or amount of charge that flows through the transverse section of the conductor in one hour. Ampere
Voltage- a physical quantity, numerically equal to the current electric field when moving a charge, up to the value of the charge. Volt
The force of the current on the conductor is directly proportional to the voltage at the ends of the conductor.
Opir- a physical quantity that characterizes the greater or lesser power of the conductor to influence the passage of the charge.
l – conductor's supper
S– area of the transverse cross-section of the conductor
– the pitomy of the opera (to be found in the guide material) is given in the tables!
Ohm's law for a lantsug plot:
R value- Constant for this conductor => do not lie down in I and U.
A rheostat is a device for regulating the strength of the struma in the lancet.
| Serial connection of conductors | Parallel connection of conductors |
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Electric strum robot
The tightness of the electric current is a physical quantity that characterizes the fluidity of the robot that operates.
Abo - in practice
Joule-Lenz law: (heating of the conductor)
A short circuit is the connection of the ends of the lancet plot with a conductor, which has very little support against the support of the lancet plot.
Electromagnetic boxes
The magnetic field remains active as long as there is some kind of conductor behind the stream, then. around the charges that are collapsing.
Charge them up, they're collapsing(charged particles) - magnetic field core
Zobraziti m.p. possible with the help of magnetic (power) lines. Magnetic lines close on themselves (do not move end to end) or go from infinity to infinity.
Magnetic field of the conductor with the strum:
To designate directly the line m. Fields are adjusted according to two rules:
1) gimlet rule
If the forward handle of the gimlet runs directly against the flow of the conductor, then the wraparound handle of the gimlet runs directly against the lines of the magnetic field.
2) right hand girth rule
If the thumb of the right hand is directed directly at the struma, then 4 fingers point directly at the line of the magnetic field.
Magnetic field of the coil with the strum:
In the middle of the coil the lines are parallel and do not fray. From now on we will go from day to day. The struma points directly to the inferior pole.
You can find out the direction of the magnetic field lines in the middle of the coil for help right hand rules:
If you point the 4 fingers of your right hand straight at the coil of the coil (touch the coil along the coil), the thumb finger will point straight at the line of the magnetic field in the middle of the coil.
A coil with a core in the middle is called - electromagnet
Permanent magnets:
The magnetic field of a stationary magnet is formed by Ampere ring struma. (Wrapping electrons in speech atoms in one place)
The Earth's magnetic poles are not aligned with its geographic poles.
Sun magnetic pole - N (sunday geog. Pole)
Subsurface magnetic pole - S (subsurface geog. Pole)
Strength characteristics of the magnetic field
Magnetic induction vector B.
The vector is a fraction of the magnetic field line and straightening as well as the magnetic field line.
The effect of the magnetic field contained in a new body:
| Conductor with strum | Part is charged |
| Left hand rule | |
| Ampere power | Lorentz force |
| I– the strength of the stream to the conductor B- magnetic induction l – conductor's dowzhna, which is located at the m.p. | q – charge of the part (behind the module) C V- fluidity of parts B – magnetic induction |
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| If you move your left hand so that the lines of the magnetic field enter the valley, and 4 fingers point directly at the struma of the conductor, then inserting 90 degrees of the thumb will directly show the Ampere force. | If the left hand is stretched so that the lines of the magnetic field enter the valley, and 4 fingers point directly at the hand (fluidity) of a positively charged particle, then moving the thumb 90 points will directly show the Lorentz forces. (for the negative part – 4 fingers against the straight line of the part) |
Light boxes
Optics is a branch of physics that reveals light phenomena and patterns.
Light is an electromagnetic substance.
The point body is light - the size of the body that glows is much smaller than the one we evaluate.
Svetlovy Promin- The line in which the energy from the light source expands.
Shade- That area is spacious, in such a way it does not waste light from the dzherel.
Napivtin- Light comes from parts of the dzherel.
The light energy that flows between two exchanges is called with a light beam.
Laws of geom. optics:
1) 
The law of light reflection
1. The line is falling, the line is broken and perpendicular, the line is at the point of the drop, lie in the same plane.
2. Kut padinnya kutu vidbittya.
Kut padinnya- Cut between the falling edge and the perpendicular to the surface, extending at the point of falling onto the surface.
Kut image- Cut between the broken edge and the perpendicular to the surface, renewed at the point where the edge falls on the surface.
Flat mirror:
The image in a flat mirror is located behind the mirror on a straight perpendicular surface of the mirror, and the view from the mirror to the image OB is the same from the object to the mirror AT.
2) The law of broken light
The optical thickness of the middle is characterized by a varied fluidity and lightness.
When moving from one middle point to another, change your direction between the middle points break down.
1. Pass what falls, breaks and perpendicular, extends to the point of fall to between two midpoints, lie in the same plane.
2. The ratio of the sinus of this one falls to the sinus of this one, the value is constant for these two middles and is called an indicator of the bending of the other middle before the first.
As the light goes from the middle of the optically smaller to the larger middle, then the bend is always less than the fall.
The bends always “press” to the perpendicular.
As light goes from the middle of an optically thicker middle to a smaller middle, then the bend is always more than the fall.
The bends always “squeeze” between the middle sections.
Promin, straightening perpendicular to the intersection two middles, pass without broken.
The lens is a clear body, surrounded by two spherical surfaces.
Lens type:
Lenzi (behind optical authorities)
Lens optical power:
The image of any point will be a point. The image of the arrow is an arrow.
Pobudova image Any point element (point of the object) at the lens is required for two exchanges.
1) Say goodbye through the center of the lens – don't break down
2) Say goodbye, what are you going to do? parallel to the head optical axis after the lens breaks at the focus of the lens
On the webbing of these two exchanges there is a point, which is Dzherel's image.
The image of the object will look like this.
Thin lens formula:
The connection of the magnetic field with the strum calls for numerical tests to awaken the strum at the contour for the help of the magnetic field. If there is a magnetic field around the conductors from the conductors, then there may be a serious phenomenon - the emergence of an electric current in a closed conductor under the influence of the magnetic field. This idea was realized more brilliantly in 1831. The English physicist Faraday, who discovered the phenomenon of electromagnetic induction, discovered connections between electrical and magnetic objects, which served as the basis for the development of the theory of the electromagnetic field.
1. Electromagnetic induction. The phenomenon of electromagnetic induction lies in the fact that when there is any change in the magnetic flux that passes through the closed circuit of the conductor, the conductor experiences an electrical induction force (e.m.f.), screams for the appearance of an electric strum, a sound. Inductive. E.D.S. Induction also occurs in an open conductor when placed in a magnetic field, in which the conductor flows over the lines of the magnetic field.
Dosvid 1: if a solenoid closed to the galvanometer is inserted or a permanent magnet is suspended, then at the moment of its insertion or suspension the galvanometer needle is prevented from moving (the induction current is at fault); straightening the arrow when the bed is in and out of the magnet. The greater the strength of the galvanometer needle, the greater the fluidity of the rotating magnet and the coil.
Dosvid 2: The strength of the flow in circuit 1 can be changed using a rheostat. This stream creates a magnetic field that permeates circuit 2, which increases the stream, the flow of magnetic induction through circuit 2 increases. This will lead to the appearance of an induction stream in circuit 2, which is registered by a galvanometer. Electromagnetic induction can be called:
1. Changing the flow, which increases the decline in the magnetic flux through another circuit and leads to the appearance of another inductive flow in a new direction, below the first drop.
2. The induction stream can be applied to circuit 2 next to circuit 1, or another circuit to the first one.
3. Do not move contour 2 step by step, but rotate it so that it changes between the normal and the contour of the direct field.
It has been established that the value of the induction stream ( u.m.c) not to be affected by the method of changing the magnetic induction flow, And it appears to be less than the speed of your change. tobto. meanings. This law is universal. (1821r.)
Professor at the St. Petersburg University Lenz followed the connections between the direct induction stream and the nature of the magnetic flux, which led to his change: Lenz’s rule: induced in the circuit of the e.p.s. a stream screams so directly that the magnetic field of its stream interferes with changes in the magnetic flux.
For example, when circuit 2 is close to circuit 1, the current magnetic moment is generated, which is straight along the field of the stream (between the vectors and the one above). Then, on circuit 2, the force acting on circuit 1 is applied. When circuit 2 is removed from circuit 1, a force is applied, the moment of which approaches directly from the field of the stream, so that the force acting on circuit 2 is directed to circuit 1.
Lenz rejected this rule out of necessity and analyzed numerical experiments. In fact, this rule is very broad - it expresses a fundamental principle, such as a system of protection to preserve a stable state of stability and against any changes in that state.
A formula that combines Faraday's law and Lenz's rule. mathematical expression of the basic law of electromagnetic induction.
Basic law of electromagnetic induction(Faraday - Maxwell law). The electrically destructive induction force that occurs in a closed circuit is proportional to the speed of change of the magnetic flux over an hour: the number of turns in the circuit, flux consolidation, since all turns of the coil are penetrated by the same flux, then .
Respect 1. The minus sign beats Lenz's rule. Most often, in numerical calculations, this sign may be omitted.
Note 2. For a closed loop.
E.D.S. turns into volts.
To prove Faraday's law, we use the law of energy conservation. Let's look at a closed circuit in which the conductors can move. Place the contour in the same field, perpendicular to the plane of the chair and directed behind the chair. Let the conductor collapse because of the speed. The force that acts on the conductor collapses. Work to be carried out on a daily basis: . Energy is wasted on heat and work: . On the other hand, we can remove it. The value plays the role of e.p.s., because to bring about until an electric struma appears in a closed loop. Well, this value is the e.r.s. electromagnetic induction
Obviously, the magnetic flow is less in these cases, if the conductor frays lines of magnetic induction field, which is called the fluidity of the bridge as a conductor of the line of magnetic induction.
For example, with a straight-line conductor, cat. collapses in a uniform magnetic field perpendicular to the lines of magnetic induction, e.p.s. Induction at the conductor, where between the conductor and directly its fluidity.
The difference in potentials at the ends of the conductor is determined by Ohm’s law. Because There is no electrical current in the conductor, then.
Respect. In boxes of electromagnetic induction, the magnetic flow through the circuit can change as a result of the collapse of the circuit of adjacent sections, and for changes in the time of the magnetic field - this is determined by Faraday’s law. .s. Induction.
With Russian conductors in the magnetic field, this law of stagnation is no longer valid in these situations, if the analysis circuit passes through the same points conductor that is collapsing. In another case, e.r.s. The induction is determined by following the Lorentz forces that act on the voltage of the charge in the conductor, which collapses, so that it acts in the Lantzug e.p.s. appears to be the work of external forces when moving around a closed lance of a single positive charge, where the charge is moving.
butt. In the same magnetic field with an induction of 0.1 T, a rectangular frame is drawn, the straight side of which is 0.1 m long and moves perpendicularly to the line of the field induction. Significance e.r.s. Induction that occurs in the circuit.
Decision: we solve the problem in two ways, by stagnating Faraday’s law or by looking at the forces that act on the free electrons in the dart that collapses (Lorentz forces).
1. As the conductor moves, the area of the frame increases, and the magnetic flux increases. according to Faraday's law dіie e.r.s. Induction. . The “-” sign indicates that the e.r.s. The induction action in the circuit is in such a direction, when connected to it by the rule of the right screw, the normal to the circuit is parallel to vector B (straight to the back). Tobto. e.m.f. The induction and induction stream are straight along the contour opposite the year arrow.
In both cases, an inaccuracy was made: the magnetic field created by the inductive stream was not taken into account. The methods of giving the correct evidence for the minds of the great support of Lanzug are discussed.
The force of the inductive stream in a closed wire circuit with a support: . It is considered positive, since the magnetic moment of the corresponding inductive stream in the circuit creates a connection with the lines of the magnetic induction field, which directs this stream.
The nature of external forces that lead to the appearance of e.r.s. electromagnetic induction: Lorentz force, which acts on a charge that collapses in a magnetic field.
You can see a change in the magnetic flux of an unbroken circuit, for example, change the value of magnetic induction. And here the Lorentz force is equal to the current (there is no ordered flow of electric charges), and the e.m.f. blames i
I cherish you, dear readers. Nature has a lot of darkness in its own way. Some people were able to find explanations for the secrets, but others did not. Magnetic phenomena in nature appear on our earth and around us, and we simply don’t notice them.
One of these things can be done by holding a magnet in your hands and pointing it at a metal flower or a hairpin. Pobachiti, like the stench will be attracted one by one.
Many of us still remember from our school physics course that this object has a magnetic field.
I hope you have guessed what magnetic objects are? Of course, it is possible to attract other metal objects that have a magnetic field.
Let's take a look at the magnetic ore from which the magnet is formed. Such magnets, melodiously, are on every refrigerator door.
You will be interested in finding out what other magnetic natural phenomena exist? From school physics lessons we know that there are magnetic and electromagnetic fields.
Let it be known to you that the magnetic weed has been common in living nature even before our era. At this hour, a compass was created, which the Chinese emperor conquered during the course of his numerous campaigns and sea walks.
The magnet is transferred from the Chinese language like a love stone. Wonderful translation, isn't it?
Christopher Columbus, like a vikoryst magnetic compass on its paths, means that geographic coordinates flow onto the arrows in the compass. This is the result of caution in scientists until they realize that there are magnetic fields on the earth.
Influx of magnetic field into living and inanimate nature
The uniqueness of migratory birds is precisely determined by the place where they lived since ancient times. The earth's magnetic field helps them lay without harm. Those migrations of many creatures lie beneath this field of earth.
So not only birds, but also creatures like:
- Turtles
- Sea molluscs
- Salmon fish
- Salamandry
- and a lot of other creatures.
It has long been understood that in the body of living organisms there are special receptors, as well as particles of magnetite, which help to sense magnetic and electromagnetic fields.
But even if the essence itself is alive, as it is alive in the wild, to know the required orientation, we definitely cannot continue to tell.
Magnetic storms and their impact on people
We already know about the magnetic fields of our earth. The stench protects us from the influx of charged microfractures that reach us from the Sun. A magnetic storm is nothing more - a cyclical change in the earth’s electromagnetic field that protects us.
Have you ever noticed how sometimes a sharp, rapt pain shoots into the back of your head and immediately causes a severe headache? All these painful symptoms that occur in the human body indicate the presence of this natural phenomenon.
This magnetic phenomenon can last for up to 12 years, or it can be short-lived. And as noted by doctors, most of the world is already suffering from heart-related illnesses.
It has been noted that the number of heart attacks increases during a magnetic storm. It is low in everything that will lead to the appearance of magnetic drills.
So, my dear readers, please be aware of their appearance and try to avoid their greedy inheritances as best you can.
Magnetic anomalies in Russia
Throughout the vast territory of our earth there are various magnetic anomalies. Let's find out a little about them.
The scientist and astronomer P.B. Inokhodtsev, as far back as 1773, began the geographical expansion of all places in the central part of Russia. It was then that a strong anomaly was detected in the area of Kursk and Bilgorod, where the compass needle turned hot. Since 1923, the first rock was drilled into the Sverdlova, which revealed metal ores.
Yesterday and in our days with you there cannot be a date to explain the great purchases of slugs in the Kursk magnetic anomaly.
From our assistants in geography, we all know that weeding plants are still being carried out in the Gorky regions. It is unknown how the smears were left on the plain.
Brazilian magnetic anomaly
Along the ocean coast of Brazil at an altitude of over 1000 kilometers, the main part of the equipment for the aircraft that fly over this place - the aircraft and their companions use their work.
Reveal the orange. Its skin protects the flesh, and the magnetic field of the earth from the dry atmosphere protects our planet from the wasteful flow out of space. And the Brazilian anomaly is similar to a dent in this skin.
Before that, the thieves were careful more than once in this unusual place.
There are still many mysteries and the mystery of our land that must be revealed today, my friends. I want to bless you with good health and so that unpleasant magnetic phenomena will bypass you!
I trust that you have enjoyed my short look at magnetic phenomena in nature. Or perhaps you have already been wary of them, or perhaps you have sensed their effect on yourself. Write about it in your comments, it will be less fun to read about it. And today that’s all. Let me say goodbye to you and see you again.
I suggest you pre-pay for the renovation of the blog. And you can also give your rating of the article according to the 10th system, which means a number of stars. Come visit me and make friends, and this site is created especially for you. I am delighted that you will certainly find a lot of useful and useful information here.
Formulas of electricity and magnetism. The development of the fundamentals of electrodynamics begins with the electron field in a vacuum. To calculate the force of interaction between two point charges and to calculate the strength of the electric field created by a point charge, it is necessary to establish Coulomb's law. To calculate the field strengths created by extended charges (charged thread, plane, etc.), Gaus's theorem is used. For a system of electric charges it is necessary to establish the principle
When taught the “Permanent Stream”, it is necessary to look at the laws of Ohm and Joule-Lenz in all forms. When taught “Magnetism”, it is necessary to take into account that the magnetic field is generated by charges that collapse, and what happens to the charges hooting. Here we must pay respect to the Bio-Savart-Laplace law. I would especially like to apply the Lorentz force and look at the motion of a charged particle in a magnetic field.
Electrical and magnetic fields are connected by a special form of matter - an electromagnetic field. The basis of the theory of the electromagnetic field is Maxwell's theory.
Table of basic formulas for electricity and magnetism
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Physical laws, formulas, changes |
Formulas of electricity and magnetism |
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Coulomb's law: |
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Electric field strength: deḞ - power per charge q 0 , what is located at this point in the field. |
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Field strength with wind r type of field core: 1) point charge 2) an endlessly charged thread with a linear charge strength τ: 3) uniformly charged uncrossed surface with surface charge strength σ: 4) between two differently charged surfaces |
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Electric field potential: de W - potential energy of charge q 0 . |
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Field potential of a point charge at the station r in the charge: |
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Following the principle of field superposition, tension: |
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Potential: de Ē i і ϕ i- Voltage and potential at this point of the field created by the i-th charge. |
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The work of electric field forces moving a charge q from a point to a potentialϕ 1 to the point with potentialϕ 2: |
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Connection between tension and potential 1) for a non-uniform field: 2) for a single field: |
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Electrical capacity of the reinforced conductor: |
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Electrical capacity of the capacitor: |
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Electrical capacity of a flat capacitor: where S is the area of the plate (one) of the capacitor, d – stand between the plates. |
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Energy of a charged capacitor: |
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Strum power: |
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Stream thickness: where S is the area of the conductor transverse to the cross-section. |
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Conductor reference: l – conductor’s dovzhina; S – area of the transverse cut. |
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Ohm's law 1) for a single plot of lantsug: 2) for the differential form: 3) for a plot of lantsug, which is intended for EPC: De ε - EPC dzherela struma, R i r - external and internal supports of the lancet; 4) for a closed Lanzug: |
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Joule-Lenz law 1) for a single plot of lantsug perennial strum: 2) for a lancet plot with strum, which changes over time: |
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Pressure of the strum: |
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Relationship between magnetic induction and magnetic field strength: where B is the vector of magnetic induction, |
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Magnetic induction(magnetic field induction): 2) fields of endlessly long direct struma 3) the field created by the cut of the conductor and the strum |
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In this lesson, the topic is “Electromagnetic field”, we will discuss the concept of “electromagnetic field”, the features of its manifestation and parameters of this field.
We communicate via mobile phone. How is the signal transmitted? How is the signal transmitted from the space station that flew to Mars? Are you empty? So, speeches can be, but not empty, but also through which the signal is transmitted. This was called the electromagnetic field. This is not directly guarded against, but is a truly obvious object of nature.
Just as an audio signal means changing the parameters of speech, for example, the radio signal (Fig. 1), then a radio signal means changing the parameters of the EM field.
Small 1. Widening sound in the wind
The words “electric” and “magnetic” are clear to us, we have already learned about electrical boxes (Fig. 2) and magnetic boxes (Fig. 3), but why do we know the language about the electromagnetic field? We'll figure it out today.
Small 2. Electric field
Small 3. Magnetic field
Use electromagnetic boxes.
In a micro-furnace, strong electromagnetic fields are created, which change rapidly as they act on an electric charge. And as we know, there is an electric charge in the atoms and molecules of the substances (Fig. 4). The axis on the new and active electromagnetic field, the vibrating molecules begin to crumble (Fig. 5) - the temperature increases and the body heats up. X-rays, ultraviolet waves, and visible light are of the same nature.
Small 4. A water molecule is a dipole
Small 5. The collapse of molecules like an electric charge
In a microviolet stove, the electromagnetic field transmits the energy that goes into heating, visible light transmits to the eye receptors the energy that goes into activating the receptor (Fig. 6), the energy of ultraviolet waves and we go to the formation of melanin in the skin (appears in the skin, Fig. 7), and the energy of X-ray changes darkens the spittle, so you can get better images of your skeleton (Fig. 8). The electromagnetic field in all these episodes has different parameters, and therefore there is a different influx.
Small 6. Mental scheme of eye receptor activation by visible light energy
Small 7. Skin tan
Small 8. Blackening of spitting during X-ray
However, we come into contact with the electromagnetic field more and more often, and it seems that phenomena related to it have long been known.
It is clear that the electric field arises from electric charges (Fig. 9). Everything has become clearer here.
Small 9. Electric field around an electric charge
As the electric charge collapses, around it, as we expected, a magnetic field arises (Fig. 10). There’s already a power supply here: the electric charge is collapsing, next to it is the electric field, how big is the magnetic field here? One more thing: we say “the charge collapses.” However, it is possible that in one system it may collapse, and in another it may collapse (Fig. 11). So, in one system the magnetic field is absent, but not in another? This field must be carefully considered when choosing a system.
Small 10. A magnetic field is in contact with an electric charge that collapses.
Small 11. Capacity of roc charge
On the right is that there is a single electromagnetic field, and there is a single core - an electric charge. There are two warehouses there. Electric and magnetic fields are not only components of a single electromagnetic field, but they manifest themselves differently in different systems (Fig. 12).
Small 12. Show an electromagnetic field
You can choose a system in which there is not only an electric field, but only a magnetic field, or an insult at the same time. However, it is not possible to select a system in which both the electrical and magnetic storage will be zero, so that the electromagnetic field will cease to exist.
The system requires either one warehouse field, or another, or all of them at once. This is how the body collapses on the stake: as one marvels at such a body of the beast, we can see the collapse on the stake (Fig. 13), as we can see the swaying of the back and forth on the side (Fig. 14). The cutaneous projection on the entire coordinates has a circular ruch - a whole circle.
Small 13. Rukh of the body on the stake
Small 14. Body shaking every day
Small 15. Projection of circular orbits onto all coordinates
Another analogy is the design of a pyramid onto a surface. It can be designed as a trikutnik or a square. There are all sorts of different figures on the square, but the whole thing is a pyramid, as seen from different sides. Although there is no such perspective, when you look at this pyramid, you don’t know anything at all. That one looks more like a square or a tricut (Fig. 16).
Small 16. Projections of a pyramid onto a plane
Let's take a look at the conductor from the strum. In this case, the negative charges are compensated by positive ones, the electric field is almost zero (Fig. 17). The magnetic field is not equal to zero (Fig. 18), and we observed that the magnetic field in the vicinity of the conductor and the stream was distorted. Let's choose a system where any electronics that create an electric current will be indestructible. In this system, however, the electrons are disrupted by the positively charged ion of the conductor at the gate: however, the magnetic field rises (Fig. 18).
Small 17. A conductor from a strum whose electric field is equal to zero
Small 18. Magnetic field around the conductor and the stream
If the electrons were in a vacuum, in this system there would be an electric field around them, and even if they were not compensated by positive charges, there would be no promagnetic field (Fig. 19).
Small 19. The electric field around electrons is the same as around vacuum
Let's take a look at a different butt. Let's take a permanent magnet. Next to it there is a magnetic field, but there is no electric field. In fact, the electric field of protons and electrons is compensated (Fig. 20).
Small 20. Magnetic field near a stationary magnet
Let's take a system in general, where a magnet collapses. In front of a stationary magnet that collapses, there is an eddy electric field (Fig. 21). Yak yogo viyaviti? The metal ring will fit according to the strength of the magnet (it will not be damaged in the system). In this case, the phenomenon of electromagnetic induction is well known: when the magnetic flux changes, an electric field arises, which leads to a collapse of charges, until a strum appears (Fig. 22). In one system there is no electric field, but in another it manifests itself.
Small 21. Vortex electric field in front of a stationary magnet that collapses.
Small 22. The phenomenon of electromagnetic induction
Magnetic field of a stationary magnet
Any kind of electron that wraps around the core can be thought of as a small electric current flowing through the stake (Fig. 23). This means that the magnetic field will remain in place for a long time. Since the substance does not magnetize, the wrapping areas of the electrons are quite straightened and the magnetic fields of the surrounding electrons compensate one another, the fragments are straightened chaotically.
Small 23. Submission of electron wrapping around the nucleus
In magnetic shells, the electron wrapping surfaces are oriented approximately the same (Fig. 24). Therefore, the magnetic fields from all electrons add up and a non-zero magnetic field emerges on the scale of the whole magnet.
Small 24. Wrapping electrons in magnetic fluxes
Around a stationary magnet there is a magnetic field, or more precisely a magnetic storehouse of an electromagnetic field (Fig. 25). How can we know such a system in which the magnetic storage is reset and the magnet loses its power? Still no. And indeed, the electrons are wrapped in the same plane (div. Fig. 24), at any moment the fluidity of the electrons is not straight in that same direction (Fig. 26). It is impossible to find out the system in detail, otherwise everything will freeze and the magnetic field will disappear.
Small 25. Magnetic field near a stationary magnet
Thus, electric and magnetic fields are different manifestations of a single electromagnetic field. It is impossible to say that at a specific point in space there is only a magnetic or electric field. There may be one or the other. Everything should be kept within the system from where we can see this point.
Why have we been talking so much about electric and magnetic fields before? First of all, it happened historically: people have known about the magnet for a long time, people have long been wary of Burshtin’s electrified evil, and no one realized that these phenomena were of the same nature. In other words, the model is hand-made. In the works, where we do not care about the interconnections of the electrical and magnetic warehouses, it is easy to look at them side by side. Two charges in this system interact through the electric field - we impose Coulomb’s law on them, we don’t need to know that electrons in any system can collapse and create a magnetic field, and the problem is successfully achieved (Fig. 27). .
Small 27. Coulomb's law
The effect of the magnetic field on the charge that collapses can be seen in another model, and it also, within the framework of its stability, operates at the top of the order (Fig. 28).
Small 28. Left hand rule
Let's try to understand how the electromagnetic field interacts with each other.
Varto make sure that the exact link is completed with a folding one. This is the life of British physicist James Maxwell. We have lived in the famous 4th century of Maxwell (Fig. 29), who study at universities and gain knowledge of high mathematics. Of course, we won’t kill them, but in a few simple words we’ll figure out what the stinks mean.
Small 29. Maxwell's Rivalry
Maxwell relied on the work of another physicist - Faraday (Fig. 30), who simply clearly described all the phenomena. In spite of the little ones (Fig. 31), records that helped Maxwell.
Small 31. Little things by Michael Faraday from the book “Electrics” (1852)
Faraday discovered the phenomenon of electromagnetic induction (Fig. 32). Guess why it's lying there. The alternating magnetic field generates EPC induction in the conductor. Otherwise, it seems that a changing magnetic field (that is, a non-electric charge) gives rise to an electric field. The entire electric field is vortex, so the lines are closed (Fig. 33).
Small 32. Michael Faraday's little ones until the end
Small 33. Blame of EPC induction in the conductor
In addition, we know that a magnetic field is generated by an electric charge, which collapses. It would be more correct to say that it is generated by a changing electric field. As the charge depletes, the electric field at the skin point changes, and this change gives rise to a magnetic field (Fig. 34).
Small 34. The origin of the magnetic field
You can notice the appearance of a magnetic field between the plates of the capacitor. When the plates are charged or discharged, an alternating electric field is generated between the plates, which in turn generates a magnetic field. In this case, the magnetic field lines lie at a plane perpendicular to the electric field lines (Fig. 35).
Small 35. Appearance of a magnetic field between the capacitor plates
And now let’s look at Maxwell’s rhyme (small 29), a short transcript of it is given below for your understanding.
The icon - divergence - is a mathematical operator, it shows that the warehouse field is like a jigsaw, so that the field lines begin and end. Marvel at another level: this storehouse of the magnetic field is equal to zero: the lines of the magnetic field do not begin or end anywhere, there is no magnetic charge. Marvel first: such a warehouse of the electric field is proportional to the strength of the charge. An electric field is created by an electric charge.
The greatest success comes in two years. The icon – rotor – is a mathematical operator that shows the vortex storage field. The third line means that the vortex electric field is created by a magnetic field that changes in an hour (this is similar, as you know from mathematics, means the speed of change of the magnetic field). Then we talk about electromagnetic induction.
The fourth study shows that respect for the proportionality coefficient is not lost: the vortex magnetic field is created by the electric field, which changes, as well as by the electric stream (the strength of the stream). Let's talk about what we know well: a magnetic field is created by an electric charge, which collapses, and.
As you see, an alternating magnetic field can generate alternating electric fields, and an alternating electric field can also generate alternating magnetic fields (Fig. 36).
Small 36. An alternating magnetic field can generate alternating electricity, and
As a result, the space may create electromagnetic interference (Fig. 37). These substances may manifest themselves in different ways - radio waves, visible light, ultraviolet radiation, and so on. We'll talk about this in upcoming lessons.
Small 37. Electromagnetic coil
List of references
- Kasyanov V.A. physics. 11th grade: Navch. for backlighting. installation - M: Bustard, 2005.
- Myakishev G.Ya. Physics: Beg. for 11th grade zagalnosvit. installation - M: Prosvitnitstvo, 2010.
- Internet portal “studopedia.su” ()
- Internet portal “worldofschool.ru” ()
Home improvement
- How can one detect a magnetic field in a system connected to one of the electrons that are uniformly collapsing in the current that is created in the kinescope of a TV set?
- What field arises from the electron that is collapsing in this system due to steady fluidity?
- What kind of field can be seen around an indestructible burshtin charged with static electricity? Besides, what is collapsing? Wrap the lines.
