Induction current strength. The strength of the induction current depends on the rate of change of the magnetic flux: the faster the magnetic flux changes, the greater the strength of the induction current.
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“Self-induction and inductance” - Manifestation of the phenomenon of self-induction. The phenomenon of EMF occurrence. Self-induced emf. Magnitude. Conductor. Units. Conclusion in electrical engineering. Current magnetic field energy. Inductance. Magnetic flux through the circuit. Magnetic field energy. Coil inductance. Self-induction. Magnetic flux.
“Electromagnetic Faraday induction” - problem solving linear structure. Appearance generator The principle of operation of the generator. Systematize knowledge. Magnet movement time. Discovered by Faraday. Questions. Induction current. Physical education minute. EMR phenomenon. Experience. The phenomenon of electromagnetic induction.
"Electromagnetic induction" - Michael Faraday. Video fragment. Magnetic needle. Conductor. Story. Alternator. Sinkwine. The phenomenon of electromagnetic induction. Contactless battery charging. Test sheet with tasks. Northern tip of the arrow. Electromagnetic induction and device. Grade. Level. Material. Faraday's experiments.
““The phenomenon of electromagnetic induction” physics” - Foucault currents (eddy currents). The induced current is caused by a change in the flux of the magnetic induction vector. The essence of the phenomenon of electromagnetic induction. An induced emf occurs in the adjacent circuit. Mutual inductance of two coils - a transformer. The plate will almost stop. The work of moving a unit charge along a closed circuit.
“Study of electromagnetic induction” - Questions and assignments. The phenomenon of electromagnetic induction. Direction of induction current. Induction current strength. Law of electromagnetic induction. The strength of the induction current depends on the rate of change of the magnetic flux. Statement. Portrait of Michael Faraday. Self-induction. Faraday's assistant. Electric field.
“Study of the phenomenon of electromagnetic induction” - Resultant field. Lorentz force. Vortex electric field. Electric motor. Increasing flow. Alternating magnetic field. The phenomenon of electromagnetic induction. Differences between vortex electric field from electrostatic. Force acting on an electron. Currents (Foucault currents) are closed in volume. Lenz's rule.
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Topic 11. PHENOMENON OF ELECTROMAGNETIC INDUCTION.
11.1. Faraday's experiments. Induction current. Lenz's rule. 11.2. The magnitude of the induced emf.
11.3. The nature of induced emf.
11.4. Circulation of the vortex electric field strength vector.
11.5. Betatron.
11.6. Toki Fuko.
11.7. Skin effect.
11.1. Faraday's experiments. Induction current. Lenz's rule.
WITH Since the discovery of the connection between the magnetic field and the current (which confirms the symmetry of the laws of nature), numerous attempts have been made to obtain current using a magnetic field. The problem was solved by Michael Faraday in 1831. (The American Joseph Henry also discovered, but did not have time to publish his results. Ampere also claimed the discovery, but was not able to present his results).
Michael Faraday (1791 - 1867) - famous English physicist. Research in the field of electricity, magnetism, magnetooptics, electrochemistry. Created a laboratory model of an electric motor. He opened the extra currents when closing and opening the circuit and established their direction. He discovered the laws of electrolysis, was the first to introduce the concepts of field and dielectric constant, and in 1845 he used the term “magnetic field.”
Among other things, M. Faraday discovered the phenomena of dia and paramagnetism. He found that all materials in a magnetic field behave differently: they are oriented along the field (steam and ferromagnets) or across
fields are diamagnetic.
Faraday's experiments are well known from the school physics course: the coil and permanent magnet(Fig.11.1)
Rice. 11.1 Fig. 11.2
If you bring a magnet close to a coil or vice versa, then a electricity. It’s the same with two closely spaced coils: if you connect an alternating current source to one of the coils, then alternating current will also appear in the other
(Fig. 11.2), but this effect is best manifested if two coils are connected with a core (Fig. 11.3).
According to Faraday's definition, what these experiments have in common is that: if the flow
As the induction vector penetrating the closed, conducting circuit changes, an electric current arises in the circuit.
This phenomenon is called the phenomenon of electromagnetic induction, and the current is induction . Moreover, the phenomenon is completely independent of the method of changing the flux of the magnetic induction vector.
So, it turns out that moving charges (current) create a magnetic field, and a moving magnetic field creates an (eddy) electric field and, in fact, an induced current.
For each specific case, Faraday indicated the direction of the induction current. In 1833 Lenz established a general rule for finding the direction of current:
the induced current is always directed in such a way that the magnetic field of this current prevents the change in magnetic flux causing the induced current. This statement is called Lenz's rule.
Filling the entire space with a homogeneous magnet leads, other things being equal, to an increase in induction by µ times. This fact confirms that
the induced current is caused by a change in the flux of the magnetic induction vector B, and not the flux of the intensity vector H.
11.2. The magnitude of the induced emf.
To create current in a circuit, an electromotive force must be present. Therefore, the phenomenon of electromagnetic induction indicates that when the magnetic flux changes in the circuit, an electromotive force of induction E i arises. Our
task, using the laws of conservation of energy, find the value E i and find out it
Let's consider the movement of the moving section 1 - 2 of the circuit with current in a magnetic field
B (Fig. 11.4).
Let first there be no magnetic field B. A battery with an emf equal to E 0 creates
current I 0 . During time dt, the battery does work
dA = E I0 dt(11.2.1)
– this work will turn into heat, which can be found according to the Joule-Lenz law:
Q = dA = E 0 I0 dt = I0 2 Rdt,
here I 0 = E R 0, R is the total resistance of the entire circuit.
Let's place the circuit in a uniform magnetic field with induction B. LinesB ||n and are related to the direction of the current by the gimlet rule. FluxF associated with the circuit is positive.r
Each contour element experiences a mechanical force d F . The moving side of the frame will experience a force F 0 . Under the influence of this force, section 1 – 2
will move with speed υ = dx dt. In this case, the magnetic flux will also change.
induction.
Then, as a result of electromagnetic induction, the current in the circuit will change and become
resulting). This force will produce work dA in time dt: dA = Fdx = IdФ.
As in the case when all elements of the frame are stationary, the source of work is E 0 .
With a stationary circuit, this work was reduced only to the release of heat. In our case, heat will also be released, but in a different amount, since the current has changed. In addition, mechanical work is performed. General work for time dt, is equal to:
E 0 Idt = I2 R dt + I dФ | ||||||||||||||
Multiply the left and right sides of this expression by | We get |
|||||||||||||
We have the right to consider the resulting expression as Ohm’s law for a circuit in which, in addition to the source E 0, E i acts, which is equal to:
Induction EMF of the circuit (E i) | equal to the rate of change of magnetic flux |
|||
induction running through this circuit.
This expression for the induced emf of a circuit is completely universal, independent of the method of changing the flux of magnetic induction and is called
Faraday's law.
Sign (-) – mathematical expression Lenz's rules on the direction of induction current: the induced current is always directed so that its field
counteract the change in the initial magnetic field.
The direction of the induction current and the direction d dt Ф are related gimlet rule(Fig. 11.5).
Dimension of induced emf: [ E i ] =[ Ф ] =B c =B .t c
If the circuit consists of several turns, then we must use the concept
flux linkage (total magnetic flux):
Ψ = Ф·N,
where N is the number of turns. So if
E i = –∑ | ∑Ф i |
|||||
i= 1 | ||||||
∑ Ф = Ψ | ||||||
Ei = − | ||||||
11.3. The nature of induced emf.
Let's answer the question: what is the reason for the movement of charges, the reason for the occurrence of induction current? Consider Figure 11.6.
1) If you move a conductor in a uniform magnetic field B, then under the influence of the Lorentz force, electrons will be deflected downward, and positive charges upward - a potential difference arises. This will be the E i -sided force, under the influence
which current flows. As we know, for positive charges
F l = q + ; for electrons F l = –e - .
2) If the conductor is stationary and the magnetic field changes, what force excites the induced current in this case? Let's take an ordinary transformer (Fig. 11.7).
As soon as we close the circuit of the primary winding, a current immediately arises in the secondary winding. But the Lorentz force has nothing to do with it, because it acts on moving charges, and at the beginning they were at rest (they were in thermal motion - chaotic, but here we need directed motion).
The answer was given by J. Maxwell in 1860: Any alternating magnetic field excites an electric field (E") in the surrounding space. This is the reason for the occurrence of induction current in the conductor. That is, E" occurs only in the presence of an alternating magnetic field (the transformer does not work at direct current).
The essence of the phenomenon of electromagnetic induction not at all in the appearance of induction current (current appears when there are charges and the circuit is closed), and in the emergence of a vortex electric field (not only in the conductor, but also in the surrounding space, in vacuum).
This field has a completely different structure than the field created by charges. Since it is not created by charges, the lines of force cannot begin and end on charges, as we did in electrostatics. This field is a vortex, its lines of force are closed.
Since this field moves charges, it therefore has force. Let's introduce
vector of the vortex electric field strength E ". The force with which this field acts on the charge
F "= q E ".
But when a charge moves in a magnetic field, it is acted upon by the Lorentz force
F" = q. | |
These forces must be equal due to the law of conservation of energy: | |
q E " = − q , hence, | |
E" = − [ vr , B] . | |
here v r is the speed of movement of the charge q relative to B. But | for the phenomenon |
The rate of change of the magnetic field B is important for electromagnetic induction. That's why |
|
can be written: | |
E " = − , | |
A MAGNETIC FIELD
The magnetic interaction of moving electric charges, according to the concepts of field theory, is explained as follows: every moving electric charge creates a magnetic field in the surrounding space that can act on other moving electric charges.
IN - physical quantity, which is the strength characteristic of the magnetic field. It is called magnetic induction (or magnetic field induction).
Magnetic induction- vector quantity. The magnitude of the magnetic induction vector is equal to the ratio of the maximum value of the Ampere force acting on a straight conductor with current to the current strength in the conductor and its length:
Unit of magnetic induction. In the International System of Units, the unit of magnetic induction is taken to be the induction of a magnetic field in which for each meter of conductor length at a current strength of 1 A maximum strength Ampere 1 N. This unit is called tesla (abbreviated: T), in honor of the outstanding Yugoslav physicist N. Tesla:
LORENTZ FORCE
The movement of a current-carrying conductor in a magnetic field shows that the magnetic field acts on moving electric charges. Ampere force acts on the conductor F A = IBlsin a, and the Lorentz force acts on a moving charge:
Where a- angle between vectors B and v.
Movement of charged particles in a magnetic field. In a uniform magnetic field, a charged particle moving at a speed perpendicular to the magnetic field induction lines is acted upon by a force m, constant in magnitude and directed perpendicular to the velocity vector. Under the influence of a magnetic force, the particle acquires acceleration, the modulus of which is equal to:
In a uniform magnetic field, this particle moves in a circle. The radius of curvature of the trajectory along which the particle moves is determined from the condition from which it follows,
The radius of curvature of the trajectory is a constant value, since a force perpendicular to the velocity vector changes only its direction, but not its magnitude. And this means that this trajectory is a circle.
The period of revolution of a particle in a uniform magnetic field is equal to:
The last expression shows that the period of revolution of a particle in a uniform magnetic field does not depend on the speed and radius of its trajectory.
If the electric field strength is zero, then the Lorentz force l is equal to the magnetic force m:
ELECTROMAGNETIC INDUCTION
The phenomenon of electromagnetic induction was discovered by Faraday, who established that an electric current arises in a closed conducting circuit with any change in the magnetic field penetrating the circuit.
MAGNETIC FLUX
Magnetic flux F(flux of magnetic induction) through a surface of area S- a value equal to the product of the magnitude of the magnetic induction vector and the area S and cosine of the angle A between the vector and the normal to the surface:
Ф=BScos
In SI, the unit of magnetic flux is 1 Weber (Wb) - magnetic flux through a surface of 1 m2 located perpendicular to the direction of a uniform magnetic field, the induction of which is 1 T:
Electromagnetic induction- the phenomenon of the occurrence of electric current in a closed conducting circuit with any change in the magnetic flux penetrating the circuit.
Arising in a closed circuit, the induction current has such a direction that its magnetic field counteracts the change in magnetic flux that causes it (Lenz's rule).
LAW OF ELECTROMAGNETIC INDUCTION
Faraday's experiments showed that the strength of the induced current I i in a conducting circuit is directly proportional to the rate of change in the number of magnetic induction lines penetrating the surface bounded by this circuit.
Therefore, the strength of the induction current is proportional to the rate of change of the magnetic flux through the surface bounded by the contour:
It is known that if a current appears in the circuit, this means that external forces act on the free charges of the conductor. The work done by these forces to move a unit charge along a closed loop is called electromotive force (EMF). Let's find the induced emf ε i.
According to Ohm's law for a closed circuit
Since R does not depend on , then
The induced emf coincides in direction with the induced current, and this current, in accordance with Lenz’s rule, is directed so that the magnetic flux it creates counteracts the change in the external magnetic flux.
Law of Electromagnetic Induction
The induced emf in a closed loop is equal to the rate of change of the magnetic flux passing through the loop taken with the opposite sign:
SELF-INDUCTION. INDUCTANCE
Experience shows that magnetic flux F associated with a circuit is directly proportional to the current in that circuit:
Ф = L*I .
Loop inductance L- proportionality coefficient between the current passing through the circuit and the magnetic flux created by it.
The inductance of a conductor depends on its shape, size and properties of the environment.
Self-induction- the phenomenon of the occurrence of induced emf in a circuit when the magnetic flux changes caused by a change in the current passing through the circuit itself.
Self-induction is a special case of electromagnetic induction.
Inductance - value, numerically equal to emf self-induction that occurs in a circuit when the current in it changes by one per unit of time. In SI, the unit of inductance is taken to be the inductance of a conductor in which, when the current strength changes by 1 A in 1 s, a self-inductive emf of 1 V occurs. This unit is called henry (H):
MAGNETIC FIELD ENERGY
The phenomenon of self-induction is similar to the phenomenon of inertia. Inductance plays the same role when changing current as mass does when changing the speed of a body. The analogue of speed is current.
This means that the energy of the magnetic field of the current can be considered a value similar to kinetic energy body:
Let us assume that after disconnecting the coil from the source, the current in the circuit decreases with time according to a linear law.
The self-induction emf in this case has a constant value:
where I is the initial value of the current, t is the time period during which the current strength decreases from I to 0.
During time t, an electric charge passes through the circuit q = I cp t. Because I cp = (I + 0)/2 = I/2, then q=It/2. Therefore, the work of electric current is:
This work is done due to the energy of the magnetic field of the coil. Thus we again get:
Example. Determine the energy of the magnetic field of the coil in which, at a current of 7.5 A, the magnetic flux is 2.3 * 10 -3 Wb. How will the field energy change if the current strength is halved?
The energy of the magnetic field of the coil is W 1 = LI 1 2 /2. By definition, the inductance of the coil is L = Ф/I 1. Hence,
Physics teacher, Secondary School No. 58, Sevastopol, Safronenko N.I.
Lesson topic: Faraday's experiments. Electromagnetic induction.
Laboratory work “Study of the phenomenon of electromagnetic induction”
Lesson Objectives : Know/understand: definition of the phenomenon of electromagnetic induction. Be able to describe and explain electromagnetic induction,be able to make observations natural phenomena, use simple measuring instruments to study physical phenomena.
- developing: develop logical thinking, cognitive interest, observation.
- educational: To form confidence in the possibility of knowing nature,necessitywise use of scientific achievements for further development human society, respect for the creators of science and technology.
Equipment: Electromagnetic induction: a coil with a galvanometer, a magnet, a coil with a core, a current source, a rheostat, a coil with a core through which alternating current flows, a solid and a ring with a slot, a coil with a light bulb. Film about M. Faraday.
Lesson type: combined lesson
Lesson method: partially search, explanatory and illustrative
§21(pp.90-93), answer questions orally p.90, test 11 p.108
Laboratory work
Study of the phenomenon of electromagnetic induction
Goal of the work: to figure out
1) under what conditions does an induced current appear in a closed circuit (coil);
2) what determines the direction of the induction current;
3) what does the strength of the induction current depend on?
Equipment : milliammeter, coil, magnet
During the classes.
Connect the ends of the coil to the terminals of the milliammeter.
1. Find out what An electric current (induction) in a coil occurs when the magnetic field inside the coil changes. Changes in the magnetic field inside the coil can be caused by moving a magnet into or out of the coil.
A) Insert the magnet with the south pole into the coil and then remove it.
B) Insert the magnet with the north pole into the coil and then remove it.
When the magnet moves, does a current (induction) appear in the coil? (When the magnetic field changes, does an induced current appear inside the coil?)
2. Find out what the direction of the induction current depends on the direction of movement of the magnet relative to the coil (the magnet is added or removed) and on which pole the magnet is inserted or removed.
A) Insert the magnet with the south pole into the coil and then remove it. Observe what happens to the milliammeter needle in both cases.
B) Insert the magnet with the north pole into the coil and then remove it. Observe what happens to the milliammeter needle in both cases. Draw the direction of deflection of the milliammeter needle:
Magnet poles
To reel
From the reel
South Pole
North Pole
3. Find out what the strength of the induction current depends on the speed of the magnet (the rate of change of the magnetic field in the coil).
Slowly insert the magnet into the coil. Observe the milliammeter reading.
Quickly insert the magnet into the coil. Observe the milliammeter reading.
Conclusion.
During the classes
The road to knowledge? She's easy to understand. You can simply answer: “You make mistakes and make mistakes again, but less, less each time. I hope that today's lesson will be one less on this road of knowledge. Our lesson is devoted to the phenomenon of electromagnetic induction, which was discovered by the English physicist Michael Faraday on August 29, 1831. It is a rare case when the date of a new remarkable discovery is known so accurately!
The phenomenon of electromagnetic induction is the phenomenon of the occurrence of electric current in a closed conductor (coil) when the external magnetic field inside the coil changes. The current is called induction. Induction - guidance, receiving.
The purpose of the lesson: study the phenomenon of electromagnetic induction, i.e. under what conditions does an induction current appear in a closed circuit (coil); find out what determines the direction and magnitude of the induction current.
At the same time as studying the material, you will perform laboratory work.
At the beginning of the 19th century (1820), after the experiments of the Danish scientist Oersted, it became clear that electric current creates a magnetic field around itself. Let's remember this experience again. (A student tells Oersted's experiment ). After this, the question arose about whether it was possible to obtain current using a magnetic field, i.e. perform the reverse action. In the first half of the 19th century, scientists turned to just such experiments: they began to look for the possibility of creating an electric current due to a magnetic field. M. Faraday wrote in his diary: “Convert magnetism into electricity.” And I walked towards my goal for almost ten years. He coped with the task brilliantly. As a reminder of what he should always think about, he carried a magnet in his pocket. With this lesson we will pay tribute to the great scientist.
Let's remember Michael Faraday. Who is he? (A student talks about M. Faraday ).
The son of a blacksmith, a newspaper delivery man, a book binder, a self-taught person who independently studied physics and chemistry from books, a laboratory assistant of the outstanding chemist Devi and finally a scientist, he did a lot of work, showed ingenuity, perseverance, and perseverance until he received an electric current using a magnetic field.
Let's take a trip to those distant times and reproduce Faraday's experiments. Faraday is considered the largest experimentalist in the history of physics.
N S
1) 2)
SN
The magnet was inserted into the coil. When the magnet moved in the coil, a current (induction) was recorded. The first scheme was quite simple. Firstly, M. Faraday used a coil with a large number turns. The coil was connected to a milliammeter device. It must be said that in those distant times there were not enough good instruments for measuring electric current. Therefore, we used unusual technical solution: they took a magnetic needle, placed a conductor next to it through which current flowed, and by the deviation of the magnetic needle they judged the flow of current. We will judge the current based on the readings of the milliammeter.
Students reproduce the experiment, perform step 1 in laboratory work. We noticed that the milliammeter needle deviates from its zero value, i.e. shows that a current appears in the circuit when the magnet moves. As soon as the magnet stops, the arrow returns to the zero position, i.e. there is no electric current in the circuit. Current appears when the magnetic field inside the coil changes.
We came to what we talked about at the beginning of the lesson: we received an electric current using a changing magnetic field. This is the first merit of M. Faraday.
The second merit of M. Faraday is that he established what the direction of the induction current depends on. We will establish this too.Students perform step 2 in laboratory work. Let's turn to point 3 of the laboratory work. Let's find out that the strength of the induction current depends on the speed of movement of the magnet (the rate of change of the magnetic field in the coil).
What conclusions did M. Faraday make?
Electric current appears in a closed circuit when the magnetic field changes (if the magnetic field exists but does not change, then there is no current).
The direction of the induction current depends on the direction of movement of the magnet and its poles.
The strength of the induction current is proportional to the rate of change of the magnetic field.
M. Faraday's second experiment:
I took two coils on a common core. I connected one to a milliammeter, and the second using a key to a current source. As soon as the circuit was closed, the milliammeter showed the induced current. When it opened, it also showed current. While the circuit is closed, i.e. there is current flowing in the circuit, the milliammeter did not show any current. The magnetic field exists, but does not change.
Let's consider a modern version of M. Faraday's experiments. We insert and remove an electromagnet and a core into a coil connected to a galvanometer, turn the current on and off, and use a rheostat to change the current strength. A coil with a light bulb is placed on the core of the coil through which alternating current flows.
Found out conditions occurrence of induction current in a closed circuit (coil). And what iscause its occurrence? Let us recall the conditions for the existence of electric current. These are: charged particles and electric field. The fact is that a changing magnetic field generates an electric field (vortex) in space, which acts on free electrons in the coil and sets them in directional motion, thus creating an induction current.
The magnetic field changes, the number of magnetic field lines through a closed loop changes. If you rotate the frame in a magnetic field, an induced current will appear in it.Show generator model.
The discovery of the phenomenon of electromagnetic induction had great value for the development of technology, for the creation of generators with the help of which electrical energy is generated, which are based on energy industrial enterprises(power plants).A film about M. Faraday “From electricity to power generators” is shown from 12.02 minutes.
Transformers operate on the phenomenon of electromagnetic induction, with the help of which they transmit electricity without loss.A power line is on display.
The phenomenon of electromagnetic induction is used in the operation of a flaw detector, with the help of which steel beams and rails are examined (inhomogeneities in the beam distort the magnetic field and an induction current appears in the flaw detector coil).
I would like to remember the words of Helmholtz: “As long as people enjoy the benefits of electricity, they will remember the name of Faraday.”
“Let those be holy who, in creative fervour, exploring the whole world, discovered laws in it.”
I think that on our road of knowledge there are even fewer mistakes.
What new did you learn? (That current can be obtained using a changing magnetic field. We found out what the direction and magnitude of the induction current depends on).
What have you learned? (Receive induced current using a changing magnetic field).
Questions:
A magnet is pushed into the metal ring during the first two seconds, during the next two seconds it is motionless inside the ring, and during the next two seconds it is removed. At what time intervals does current flow in the coil? (From 1-2s; 5-6s).
A ring with or without a slot is put on the magnet. Where does induced current occur? (In a closed ring)
On the core of the coil, which is connected to an alternating current source, there is a ring. The current is turned on and the ring jumps. Why?
Board design:
"Turn magnetism into electricity"
M. Faraday
Portrait of M. Faraday
Drawings of M. Faraday's experiments.
Electromagnetic induction is the phenomenon of the occurrence of electric current in a closed conductor (coil) when the external magnetic field inside the coil changes.
This current is called induction current.
Induction current is a current that occurs in a closed conductive circuit located in an alternating magnetic field. This current can occur in two cases. If there is a stationary circuit penetrated by a changing flux of magnetic induction. Or when a conducting circuit moves in a constant magnetic field, which also causes a change in the magnetic flux penetrating the circuit.
Figure 1 - A conductor moves in a constant magnetic field
The cause of the induction current is the vortex electric field, which is generated by the magnetic field. This electric field acts on free charges located in a conductor placed in this vortex electric field.
Figure 2 - vortex electric field
You can also find this definition. Induction current is an electric current that arises due to the action of electromagnetic induction. If you don’t delve into the intricacies of the law of electromagnetic induction, then in a nutshell it can be described as follows. Electromagnetic induction is the phenomenon of the occurrence of current in a conducting circuit under the influence of an alternating magnetic field.
Using this law, you can determine the magnitude of the induction current. Since it gives us the value of the EMF that occurs in the circuit under the influence of an alternating magnetic field.
Formula 1 - EMF of magnetic field induction.
As can be seen from formula 1, the magnitude of the induced emf, and therefore the induced current, depends on the rate of change of the magnetic flux penetrating the circuit. That is, the faster the magnetic flux changes, the greater the induction current can be obtained. In the case when we have a constant magnetic field in which the conducting circuit moves, the magnitude of the EMF will depend on the speed of movement of the circuit.
To determine the direction of the induction current, Lenz's rule is used. Which states that the induced current is directed towards the current that caused it. Hence the minus sign in the formula for determining the induced emf.
Induction current plays an important role in modern electrical engineering. For example, the induced current generated in the rotor of an induction motor interacts with the current supplied from the power source in its stator, causing the rotor to rotate. Modern electric motors are built on this principle.
Figure 3 - asynchronous motor.
In a transformer, the induction current arising in the secondary winding is used to power various electrical devices. The magnitude of this current can be set by the transformer parameters.
Figure 4 - electrical transformer.
And finally, induced currents can also arise in massive conductors. These are the so-called Foucault currents. Thanks to them, it is possible to perform induction melting of metals. That is, eddy currents flowing in the conductor cause it to heat up. Depending on the magnitude of these currents, the conductor can heat up above the melting point.
Figure 5 - induction melting of metals.
So, we found out that induced current can have mechanical, electrical and thermal effect. All these effects are widely used in modern world, both on an industrial scale and at the household level.
