Educational film, television and video recording have much in common. These means make it possible to show a phenomenon in dynamics, which is, in principle, inaccessible to static screen means. This feature is put at the forefront by all researchers in the field of technical teaching aids.
Movement in cinema cannot be reduced only to mechanical movement objects on the screen. Thus, in many films on art and architecture, the dynamics consist of individual static images, when not the subject itself changes, but the camera position, scale, one image is superimposed on another, for example, a photograph of it is superimposed on the task diagram. By using the specific capabilities of cinema, in many films one can see manuscripts “come to life”, in which lines of text appear from under an invisible (or visible) pen. Thus, the dynamics in cinema are also the dynamics of cognition, thought, and logical constructions.
Of great importance are such properties of these teaching aids as slowing down and accelerating the passage of time, changing space, turning invisible objects into visible ones. The special language of cinema, which is “spoken” not only by films shot on film, but also by messages created and transmitted by means of television or “canned” in a video cassette, determines situations in the lesson when the use of cinema (understood in in a broad sense) turns out to be didactically justified. So, N.M. Shakhmaev identifies 11 cases, pointing out that this is not an exhaustive list.
1. Study of objects and processes observed using optical and electron microscopes, not currently available to the school. In this case, film materials, filmed in special laboratories and provided with qualified comments from a teacher or speaker, have scientific reliability and can be shown to the whole class.
2. When studying fundamentally invisible objects, such as, for example, elementary particles and the fields surrounding them. Using animation, you can show the model of an object and even its structure. The pedagogical value of such model representations is enormous, because they create in the minds of students certain images of objects and mechanisms of complex phenomena, which facilitates the understanding of educational material.
3. When studying such objects and phenomena that, due to their specific nature, cannot be visible simultaneously to all students in the class. By using special optics and choosing the most advantageous shooting points, you can photograph these objects close-up, cinematically highlight and explain.
4. When studying rapidly or slowly occurring phenomena. Fast or slow
filming, combined with normal projection speed, transforms the passage of time and makes these processes observable.
5. When studying processes occurring in places inaccessible to direct observation (volcano crater; underwater world of rivers, seas and oceans; radiation zones; cosmic bodies, etc.). In this case, only cinema and television can provide the teacher with the necessary scientific documentation, which serves as a teaching aid.
6. When studying objects and phenomena observed in those regions of the spectrum electromagnetic waves rays that are not directly perceived by the human eye (ultraviolet, infrared and x-rays). Shooting through narrow-bandwidth filters special types films, as well as shooting from fluorescent screens, make it possible to transform an invisible image into a visible one.
7. When explaining such fundamental experiments, the staging of which in the conditions of the educational process is difficult due to the complexity or cumbersomeness of the installations, the high cost of equipment, the duration of the experiment, etc. Filming such experiments allows not only to demonstrate the progress and results, but also to provide the necessary explanations. It is also important that the experiments are shown from the most favorable point, from the most favorable angle, which cannot be achieved without cinema.
8. When explaining the structure of complex objects (structure internal organs humans, designs of machines and mechanisms, structure of molecules, etc.). In this case, with the help of animation, by gradually filling and transforming the image, you can move from the simplest diagram to a specific design solution.
9. When studying the creativity of writers and poets. Cinema makes it possible to reproduce character traits era in which the artist lived and worked, but also to show him creative path, birth process poetic image, manner of work, connection of creativity with the historical era.
10. When studying historical events. Films based on newsreel material, in addition to their own scientific significance have a tremendous emotional impact on students, which is extremely important for a deep understanding of historical events. In special feature films, thanks to the specific capabilities of cinema, it is possible to recreate historical episodes dating back to long ago. Historical accurate reproduction of objects of material culture, characters historical figures, economics, and everyday life helps to create in students a real idea of the events that they learn about from textbooks and from the teacher’s story. History takes on tangible forms and becomes a vivid, emotionally charged fact that becomes part of the student’s intellectual structure of thought.
11. To solve a large complex of educational problems.
Defining the boundaries of film, television and video recording is fraught with the danger of making mistakes. The error of improperly expanding the possibilities of using these teaching aids in educational process can be illustrated by the words of one of the characters in the film “Moscow Doesn’t Believe in Tears”: “Soon nothing will happen. It will be all television." Life has shown that books, theater, and cinema have survived. And what is most important is direct information contact between the teacher and students.
On the other hand, there may be a mistake of unreasonably narrowing the didactic functions of screen-sound teaching aids. This occurs when a film or video TV Broadcast are considered only as a type of visual aid that has the ability to dynamically represent the material being studied. This is certainly true. But besides this there is one more aspect: in didactic materials presented to students using a film projector, VCR and TV, specific learning tasks are solved not only by technology, but also by visual arts inherent in one or another type of art. Therefore, screen tutorial acquires clearly visible features of a work of art, even if it was created for academic subject, related to the natural-mathematical cycle.
It should be remembered that neither a movie, nor a video recording, nor television can create long-lasting and lasting motives for teaching, nor can they replace other means of visualization. An experiment with hydrogen carried out directly in the classroom (an explosion of detonating gas in a metal tin can) is many times more visual than the same experiment demonstrated on the screen.
1. Who was the first to demonstrate moving hand-drawn pictures on the screen to many viewers at the same time?
2. How was T. Edison’s kinetoscope designed?
4. Describe the structure of black and white film.
5. What types of filming are used in film production?
6. What features characterize educational films and videos?
7. List the requirements for the educational film.
8. What types of films can be divided into?
9. What is the seal used for?
10. What types of phonograms are used in the production of films?
Victor Kuligin
Disclosure of content and specification of concepts should be based on one or another specific model of the mutual connection of concepts. The model, objectively reflecting a certain aspect of the relationship, has limits of applicability, beyond which its use leads to false conclusions, but within the limits of its applicability it must have not only imagery, clarity and specificity, but also have heuristic value.
The variety of manifestations of cause-and-effect relationships in the material world has led to the existence of several models of cause-and-effect relationships. Historically, any model of these relationships can be reduced to one of two main types of models or a combination of them.
a) Models based on a time approach (evolutionary models). Here the main attention is focused on the temporal side of cause-and-effect relationships. One event – “cause” – gives rise to another event – “effect”, which lags behind the cause in time (lags). Lag is a hallmark of the evolutionary approach. Cause and effect are interdependent. However, reference to the generation of an effect by a cause (genesis), although legal, is introduced into the definition of a cause-and-effect relationship as if from the outside, from the outside. It captures the external side of this connection without deeply capturing the essence.
The evolutionary approach was developed by F. Bacon, J. Mill and others. The extreme polar point of the evolutionary approach was the position of Hume. Hume ignored genesis, denying the objective nature of causality, and reduced causality to the simple regularity of events.
b) Models based on the concept of “interaction” (structural or dialectical models). We will find out the meaning of the names later. The main focus here is on interaction as the source of cause-and-effect relationships. The interaction itself acts as a cause. Kant paid much attention to this approach, but the dialectical approach to causality acquired its clearest form in the works of Hegel. Of the modern Soviet philosophers, this approach was developed by G.A. Svechnikov, who sought to give a materialistic interpretation of one of the structural models of cause-and-effect relationships.
Existing and currently used models reveal the mechanism of cause-effect relationships in different ways, which leads to disagreements and creates the basis for philosophical discussions. The intensity of the discussion and the polar nature of the points of view indicate their relevance.
Let us highlight some of the issues being discussed.
a) The problem of simultaneity of cause and effect. This is the main problem. Are cause and effect simultaneous or separated by an interval of time? If cause and effect are simultaneous, then why does the cause give rise to the effect, and not vice versa? If cause and effect are not simultaneous, can there be a “pure” cause, i.e. a cause without an effect that has not yet occurred, and a “pure” effect, when the action of the cause has ended, but the effect is still ongoing? What happens in the interval between cause and effect, if they are separated in time, etc.?
b) The problem of unambiguity of cause-and-effect relationships. Does the same cause give rise to the same effect, or can one cause give rise to any effect from several potential ones? Can the same effect be produced by any of several causes?
c) The problem of the reverse influence of an effect on its cause.
d) The problem of connecting cause, occasion and conditions. Can, under certain circumstances, cause and condition change roles: the cause becomes a condition, and the condition becomes a cause? What is the objective relationship and distinctive features of cause, occasion and condition?
The solution to these problems depends on the chosen model, i.e. to a large extent, on what content will be included in the initial categories of “cause” and “effect”. The definitional nature of many difficulties is manifested, for example, in the fact that there is no single answer to the question of what should be understood by “cause.” Some researchers think of a cause as a material object, others as a phenomenon, others as a change in state, others as an interaction, etc.
Attempts to go beyond the model representation and give a general, universal definition of the cause-and-effect relationship do not lead to a solution to the problem. As an example, we can cite the following definition: “Causality is such a genetic connection of phenomena in which one phenomenon, called the cause, in the presence of certain conditions inevitably generates, causes, brings to life another phenomenon, called the effect.” This definition is formally valid for most models, but without relying on the model, it cannot solve the problems posed (for example, the problem of simultaneity) and therefore has limited theoretical-cognitive value.
When solving the problems mentioned above, most authors tend to proceed from the modern physical picture of the world and, as a rule, pay somewhat less attention to epistemology. Meanwhile, in our opinion, there are two problems here that are important: the problem of removing elements of anthropomorphism from the concept of causality and the problem of non-causal connections in natural science. The essence of the first problem is that causality as an objective philosophical category must have an objective character, independent of the cognizing subject and his activity. The essence of the second problem: whether to recognize causal connections in natural science as universal and universal, or to consider that such connections are limited in nature and that there are connections of a non-causal type that deny causality and limit the limits of applicability of the principle of causality? We believe that the principle of causality is universal and objective and its application knows no restrictions.
So, two types of models, objectively reflecting some important aspects and features of cause-effect relationships, are to a certain extent in contradiction, since they solve the problems of simultaneity, unambiguity, etc. in different ways, but at the same time, objectively reflecting some aspects of cause-effect relationships , they must be in mutual connection. Our first task is to identify this connection and refine the models.
Limit of applicability of models
Let us try to establish the limit of applicability of evolutionary type models. Causal chains that satisfy evolutionary models tend to have the property of transitivity. If event A is the cause of event B (B is a consequence of A), if, in turn, event B is the cause of event C, then event A is the cause of event C. If A → B and B → C, then A → C. Thus In this way, the simplest cause-and-effect chains are formed. Event B may act as a cause in one case, and as a consequence in another. This pattern was noted by F. Engels: “... cause and effect are representations that have meaning, as such, only when applied to a given individual case: but as soon as we consider this isolated case in a common connection with the entire world, these ideas converge and intertwine in the idea of universal interaction, in which causes and effects constantly change places; what is a cause here or now becomes an effect there or then and vice versa” (vol. 20, p. 22).
The transitivity property allows for a detailed analysis of the causal chain. It consists of dividing the final chain into simpler cause-and-effect links. If A, then A → B1, B1 → B2,..., Bn → C. But does a finite causal chain have the property of infinite divisibility? Can the number of links in a finite chain N tend to infinity?
Based on the law of the transition of quantitative changes into qualitative ones, it can be argued that when dividing the final cause-and-effect chain, we will be faced with such content of individual links in the chain that further division will become meaningless. Note that infinite divisibility, which denies the law of the transition of quantitative changes into qualitative ones, Hegel called “bad infinity”
The transition of quantitative changes into qualitative ones occurs, for example, when dividing a piece of graphite. When molecules are separated until a monatomic gas is formed, the chemical composition does not change. Further division of a substance without changing its chemical composition is no longer possible, since the next stage is the splitting of carbon atoms. Here, from a physicochemical point of view, quantitative changes lead to qualitative ones.
The above statement by F. Engels clearly shows the idea that the basis of cause-and-effect relationships is not spontaneous expression of will, not the whim of chance and not the divine finger, but universal interaction. In nature there is no spontaneous emergence and destruction of movement, there are mutual transitions of one form of motion of matter to others, from one material object to another, and these transitions cannot occur otherwise than through the interaction of material objects. Such transitions, caused by interaction, give rise to new phenomena, changing the state of interacting objects.
Interaction is universal and forms the basis of causation. As Hegel rightly noted, “interaction is a causal relation posited in its full development.” F. Engels formulated this idea even more clearly: “Interaction is the first thing that appears to us when we consider moving matter as a whole from the point of view of modern natural science... Thus, natural science confirms that... that interaction is a true causa finalis of things. We cannot go further than the knowledge of this interaction precisely because behind it there is nothing more to know” (vol. 20, p. 546).
Since interaction is the basis of causality, let us consider the interaction of two material objects, the diagram of which is shown in Fig. 1. This example does not violate the generality of reasoning, since the interaction of several objects is reduced to paired interactions and can be considered in a similar way.
It is easy to see that during interaction both objects simultaneously influence each other (reciprocity of action). In this case, the state of each of the interacting objects changes. No interaction - no change of state. Therefore, a change in the state of any one of the interacting objects can be considered as a partial consequence of the cause - interaction. A change in the states of all objects in their totality will constitute a complete consequence.
It is obvious that such a cause-and-effect model of the elementary link of the evolutionary model belongs to the class of structural (dialectical). It should be emphasized that this model does not reduce to the approach developed by G.A. Svechnikov, since under investigation G.A. Svechnikov, according to V.G. Ivanov, understood “... a change in one or all interacting objects or a change in the nature of the interaction itself, up to its collapse or transformation.” As for the change of states, this is a change in G.A. Svechnikov classified it as a non-causal type of connection.
So, we have established that evolutionary models, as an elementary, primary link, contain a structural (dialectical) model based on the interaction and change of states. Somewhat later we will return to the analysis of the mutual connection of these models and the study of the properties of the evolutionary model. Here we would like to note that, in full accordance with the point of view of F. Engels, the change of phenomena in evolutionary models reflecting objective reality occurs not due to the simple regularity of events (as in D. Hume), but due to the conditionality generated by interaction (genesis ). Therefore, although references to generation (genesis) are introduced into the definition of cause-and-effect relationships in evolutionary models, they reflect the objective nature of these relationships and have a legal basis.
Fig. 2. Structural (dialectical) model of causality
Let's return to the structural model. In its structure and meaning, it perfectly agrees with the first law of dialectics - the law of unity and struggle of opposites, if interpreted:
– unity – as the existence of objects in their mutual connection (interaction);
– opposites – as mutually exclusive tendencies and characteristics of states caused by interaction;
– struggle – as interaction;
– development – as a change in the state of each of the interacting material objects.
Therefore, a structural model based on interaction as a cause can also be called a dialectical model of causality. From the analogy of the structural model and the first law of dialectics, it follows that causality acts as a reflection of objective dialectical contradictions in nature itself, in contrast to the subjective dialectical contradictions that arise in the human mind. The structural model of causality is a reflection of the objective dialectics of nature.
Let's consider an example illustrating the application of a structural model of cause-and-effect relationships. There are quite a lot of such examples that can be explained using this model. natural sciences(physics, chemistry, etc.), since the concept of “interaction” is fundamental in natural science.
Let us take as an example an elastic collision of two balls: a moving ball A and a stationary ball B. Before the collision, the state of each of the balls was determined by a set of attributes Ca and Cb (momentum, kinetic energy, etc.). After the collision (interaction), the states of these balls changed. Let us denote the new states C"a and C"b. The reason for the change in states (Ca → C"a and Cb → C"b) was the interaction of the balls (collision); the consequence of this collision was a change in the state of each ball.
As already mentioned, the evolutionary model is of little use in this case, since we are not dealing with a causal chain, but with an elementary cause-and-effect link, the structure of which cannot be reduced to the evolutionary model. To show this, let us illustrate this example explanation from the position of the evolutionary model: “Before the collision, ball A was at rest, so the cause of its movement is ball B, which hit it.” Here ball B is the cause, and the movement of ball A is the effect. But from the same positions, the following explanation can be given: “Before the collision, ball B was moving uniformly along a straight path. If it weren’t for ball A, then the nature of the movement of ball B would not have changed.” Here the cause is already ball A, and the effect is the state of ball B. The above example shows:
a) a certain subjectivity that arises when applying the evolutionary model beyond the limits of its applicability: the cause can be either ball A or ball B; this situation is due to the fact that the evolutionary model picks out one particular branch of the consequence and is limited to its interpretation;
b) a typical epistemological error. In the above explanations from the position of the evolutionary model, one of the material objects of the same type acts as an “active” principle, and the other as a “passive” principle. It turns out that one of the balls is endowed (in comparison with the other) with “activity”, “will”, “desire”, like a person. Therefore, it is only thanks to this “will” that we have a causal relationship. Such an epistemological error is determined not only by the model of causality, but also by the imagery inherent in living human speech, and the typical psychological transfer of properties characteristic of complex causality (we will talk about it below) to a simple cause-and-effect link. And such errors are very typical when using an evolutionary model beyond the limits of its applicability. They appear in some definitions of causation. For example: “So, causation is defined as such an effect of one object on another, in which a change in the first object (cause) precedes a change in another object and in a necessary, unambiguous way gives rise to a change in another object (effect).” It is difficult to agree with such a definition, since it is not at all clear why, during interaction (mutual action!), objects should not be deformed simultaneously, but one after another? Which object should deform first and which should deform second (priority problem)?
Model qualities
Let us now consider what qualities the structural model of causality contains. Let us note the following among them: objectivity, universality, consistency, unambiguity.
The objectivity of causality is manifested in the fact that interaction acts as an objective cause in relation to which the interacting objects are equal. There is no room for anthropomorphic interpretation here. Universality is due to the fact that the basis of causality is always interaction. Causality is universal, just as interaction itself is universal. Consistency is due to the fact that, although cause and effect (interaction and change of states) coincide in time, they reflect different aspects of the cause-and-effect relationship. Interaction presupposes a spatial connection of objects, a change in state - a connection between the states of each of the interacting objects in time.
In addition, the structural model establishes an unambiguous relationship in cause-and-effect relationships, regardless of the method of mathematical description of the interaction. Moreover, the structural model, being objective and universal, does not impose restrictions on the nature of interactions in natural science. Within the framework of this model, instantaneous long- or short-range action and interaction with any finite velocities are valid. The appearance of such a limitation in determining cause-and-effect relationships would be a typical metaphysical dogma, once and for all postulating the nature of the interaction of any systems, imposing a natural philosophical framework on physics and other sciences on the part of philosophy, or it would limit the limits of applicability of the model so much that the benefits of such a model would be very modest.
Here it would be appropriate to dwell on issues related to the finiteness of the speed of propagation of interactions. Let's look at an example. Let there be two stationary charges. If one of the charges begins to move with acceleration, then the electromagnetic wave will approach the second charge with a delay. Doesn’t this example contradict the structural model and, in particular, the property of reciprocity of action, since when
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Limits of applicability of physical laws and theories
All physical laws and theories are approaching to reality, since when constructing theories a certain model phenomena and processes. Therefore, both laws and theories have certain limits of applicability .
For example, classical mechanics, based on Newton's three laws and the law of universal gravitation, is valid only when bodies move at speeds much lower than the speed of light. If the speeds of bodies become comparable to the speed of light (for example, those distant from us space objects or elementary particles in accelerators), the predictions of classical mechanics become incorrect. This is where the special theory of relativity, created at the beginning of the 20th century by Einstein, comes into play.
Second example: the behavior of the smallest particles of matter - the so-called elementary particles, as well as the structure of the atom cannot be understood within the framework of classical mechanics: it turned out that phenomena occurring at very small distances and in very short periods of time are beyond the limits of its applicability. And at the beginning of the 20th century, to explain atomic phenomena, the work of several scientists created quantum mechanics .
Third example: geometric optics, well known to you from your basic school physics course, based on the idea of light rays, is in excellent agreement with experience if the size of the objects with which the light interacts is much larger than the light wavelength. But if the size of objects is comparable to the wavelength of light or much less than it, the wave theory Sveta , which is based on the idea of light waves.
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Darcy's law is valid if the following conditions are met:
a) the porous medium is fine-grained and the pore channels are quite narrow;
b) the filtration rate and pressure gradient are low;
c) changes in filtration rate and pressure gradient are small.
With an increase in the speed of fluid movement, Darcy's law is violated due to an increase in pressure losses due to effects associated with inertial forces: the formation of vortices, zones of flow separation from the surface of particles, hydraulic shock on particles, etc. This is the so-called upper limit . Darcy's law can also be violated at very low filtration rates when the fluid begins to move due to the manifestation of non-Newtonian rheological properties of the fluid and its interaction with the solid skeleton of the porous medium. This bottom line.
Upper limit. The criterion for the upper limit of the validity of Darcy's law is usually a comparison of the Reynolds number Re=war/h with its critical importance Re cr, after which linear connection between head loss and flow is violated. In the expression for the number Re:
w-characteristic flow speed:
A- characteristic geometric size of the porous medium;
r- liquid density.
There are a number of representations of Reynolds numbers obtained by various authors with one or another justification of the characteristic parameters. Here are some of these dependencies most used in underground hydromechanics:
a) Pavlovsky
Critical Reynolds number Re cr =7.5-9.
b) Shchelkacheva
(1.31)
Critical Reynolds number Re cr =1-12.
c) Millionshchikova
(1.32)
Critical Reynolds number Re cr =0.022-0.29.
Filtration speed u cr, in which Darcy's law is violated is called critical filtration rate . Violation of the filtration rate does not mean a transition from laminar movement to turbulent, but is caused by the fact that the inertial forces arising in the liquid due to the tortuosity of the channels and changes in the cross-sectional area become at u>u cr comparable to the friction forces.
When processing experimental data to determine the critical speed, they use dimensionless Darcy parameter:
, (1.33)
representing the ratio of viscous friction forces to pressure force. In the area of Darcy's law, this parameter is equal to 1 and decreases when the number is exceeded Re critical value.
Bottom line. At very low velocities, as the pressure gradient increases (pressure changes with depth), the filtration rate increases more rapidly than according to Darcy's law. This phenomenon is explained by the fact that at low speeds the force interaction between the solid skeleton and the liquid becomes significant due to the formation of anomalous, non-Newtonian systems, etc. stable colloidal solutions in the form of gelatinous films that block pores and collapse under a certain pressure gradient t n, called initial and depending on the proportion of clay material and the value of residual water saturation. There are many rheological models of non-Newtonian fluids, the simplest of which is the limiting gradient model
(1.34)
1.3.1.4. Filtration laws for Re > Re cr
The accuracy of the well survey data and the determination of formation parameters depend on the accuracy of the filtration law used. In this regard, in the area of violation of Darcy's law, it is necessary to introduce more general, nonlinear filtration laws. These laws are divided into one-term and two-term.
