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Interesting facts about physics. Physics around us: interesting facts. it's an occupation. Topic: thermal expansion of bodies when heated. hair lengthening at a given load

If you think that physics is boring, then this article is for you. We will tell you interesting facts that will help you take a fresh look at an unloved subject.

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#1: Why is the Sun red at night?

Actually, the light from the sun is white. White light in its spectral decomposition is the sum of all the colors of the rainbow. In the evening and morning, the rays pass through the low surface and dense layers of the atmosphere. Dust particles and air molecules thus act as a red filter, best passing through the red component of the spectrum.

#2: where did atoms come from?

When the universe was formed, there were no atoms. There were only elementary particles, and even then not all. The atoms of the elements of almost the entire periodic table were formed during nuclear reactions in the interiors of stars, when lighter nuclei turn into heavier ones. We ourselves are made up of atoms formed in deep space.

#3: How much "dark" matter is there in the world?

We live in the material world and everything that is around is matter. You can touch it, sell it, buy it, you can build something. But in the world there is not only matter, but also dark matter. It does not emit electromagnetic radiation and does not interact with it.

Dark matter, for obvious reasons, has not been touched or seen. Scientists decided that it exists, observing some indirect signs. It is believed that dark matter occupies about 22% of the composition of the universe. For comparison: the good old matter familiar to us takes only 5%.

#4: What is the temperature of lightning?

And so it is clear that it is very high. According to science, it can reach 25,000 degrees Celsius. This is many times more than on the surface of the Sun (there are only about 5000). We strongly do not recommend trying to check what temperature the lightning has. There are specially trained people in the world for this.

There is! Considering the scale of the Universe, the probability of this was previously estimated quite high. But it's only relatively recently that humans have begun to discover exoplanets.

Exoplanets revolve around their stars in the so-called "life zone". More than 3,500 exoplanets are now known, and more and more are being discovered.

#6: How old is the Earth?

The earth is about four billion years old. In this context, one fact is interesting: the largest unit of time is the kalpa. Kalpa (otherwise - the day of Brahma) is a concept from Hinduism. According to him, the day is replaced by a night equal to it in duration. At the same time, the duration of the day of Brahma with an accuracy of 5% coincides with the age of the Earth.

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#7: Where Do Aurora Borealis Come From?

polar or Northern Lights- This is the result of the interaction of the solar wind (cosmic radiation) with the upper layers of the Earth's atmosphere.

Charged particles from space collide with atoms in the atmosphere, causing them to become excited and emit light. This phenomenon is observed at the poles, as the Earth's magnetic field "captures" particles, protecting the planet from being "bombarded" by cosmic rays.

#8: Is it true that the water in the sink swirls in different directions in the northern and southern hemispheres?

Actually it is not. Indeed, there is a Coriolis force acting on the fluid flow in a rotating frame of reference. On the scale of the Earth, the action of this force is so small that it is possible to observe the swirling of water during runoff in different directions only under very carefully selected conditions.

#9: How is water different from other substances?

One of the fundamental properties of water is its density in solid and liquid states. Thus, ice is always lighter than liquid water, therefore it is always on the surface and does not sink. Also, hot water freezes faster than cold water. This paradox, called the Mpemba effect, has not yet found an exact explanation.

#10: How does speed affect time?

The faster an object moves, the slower time will go for it. Here we can recall the paradox of twins, one of which traveled in an ultra-fast spacecraft, and the second remained on earth. When the space traveler returned home, he found his brother an old man. The answer to the question why this happens is given by the theory of relativity and relativistic mechanics.


We hope our 10 facts about physics helped to make sure that these are not only boring formulas, but the whole world around us.

However, formulas and tasks can be a hassle. To save time, we have collected the most popular formulas and prepared a memo for solving physical problems.

And if you are tired of strict teachers and endless tests, contact us, which will help you quickly solve even tasks of increased complexity.

"Physics around us".

Work plan:

    Physics. Concept.

    Story.

    Physics in nature.

    Physics in medicine.

    Physics and Literature.

    Physics and art.

    Conclusion.

Physics. Concept.

Physics(fromother Greekφύσις "nature") - areanatural science, a science that studies the most general and fundamental patterns that determine structure and evolution material world. The laws of physics underlie all natural science.

The term "physics" first appeared in the writings of one of the greatest thinkers of antiquity -Aristotle, who lived in the 4th century BC. Initially, the terms "physics" and "philosophy" were synonymous, since both disciplines try to explain the laws of functioningUniverse. However, as a resultscientific revolutionIn the 16th century, physics emerged as a separate scientific direction.

ATRussian languagethe word "physics" was introducedMikhail Vasilyevich Lomonosov, when he published the firstRussiaphysics textbook translated fromGerman language. The first Russian textbook called "Brief outline of physics" was written by the first Russian academicianInsurance.

In the modern world, the importance of physics is extremely high. Everything that distinguishes modernsocietyfrom the society of past centuries, appeared as a result of the practical application of physical discoveries. So, research in the fieldelectromagnetismled to the emergencephones, opening inthermodynamicsallowed to createcar, developmentelectronicsled to the advent of computers.

The physical understanding of the processes occurring in nature is constantly evolving. Most of the new discoveries soon find application in technology and industry. However, new research is constantly raising new mysteries and discovering phenomena that require new physical theories to explain. Despite the huge amount of accumulated knowledge, modern physics is still very far from being able to explain all natural phenomena.

Story

One of the main features of a person is the ability (to a certain extent) to predict future events. To do this, a person builds mental models real phenomena(theories); in case of poor predictive power, the model is refined or replaced with a new one. If you create practically utility model natural phenomena failed, it was replaced by religious myths ("lightning is the wrath of the gods").

The means to test theories and find out which one is true were very few in antiquity, even when it was about everyday earthly phenomena. The only physical quantity that could then be measured accurately enough -length; later added to itinjection. The standard of time wasdays, which Ancient Egypt divided not into 24 hours, but into 12 days and 12 nights, so there were two different hours, and in different seasons hours varied. But even when the units of time familiar to us were established, due to the lack of accurate clock most physical experiments were simply impossible to carry out. Therefore, it is natural that semi-religious teachings arose instead of scientific schools.

prevailedgeocentric system of the world, althoughPythagoreansdeveloped andpyrocentricin which the stars, sun, moon and six planets revolve aroundCentral Fire. To make everything a sacred number celestial spheres(ten), the sixth planet was announcedcounter-earth. However, individual Pythagoreans (Aristarchus of Samosetc.) createdheliocentric system. Among the Pythagoreans, for the first time, the conceptetheras a universal filler of emptiness.

The first formulation of the law of conservation of matter was proposed by Empedocles in the 5th century BC. e.:

Nothing can come from nothing, and nothing that exists can be destroyed.

Later, a similar thesis was expressedDemocritus,Aristotleother.

The term "Physics" originated as the title of one of Aristotle's writings. The subject of this science, according to the author, was to elucidate the root causes of phenomena:

Since scientific knowledge arises from all investigations that extend to principles, causes or elements by means of their knowledge (after all, we are then sure of the knowledge of any thing when we recognize its first causes, first principles and analyze it further down to elements), it is clear that and in the science of nature it is necessary first of all to determine what belongs to the principles.

This approach takes a long time (actually up toNewton) gave priority to metaphysical fantasies over experimental research. In particular, Aristotle and his followers argued that the movement of a body is supported by a force applied to it, and in its absence the body will stop (according to Newton, the body retains its speed, and the acting force changes its value and/or direction).

Some ancient schools proposed the doctrine ofatomsas the fundamental principle of matter.Epicuruseven thought thatfree willhuman is caused by the fact that the movement of atoms is subject to random displacements.

In addition to mathematics, the Hellenes successfully developed optics. Hero of Alexandria has the first variational principle of "least time" for the reflection of light. Nevertheless, there were gross errors in the optics of the ancients. For example, the angle of refraction was considered proportional to the angle of incidence (even Kepler shared this error). Hypotheses about the nature of light and color were numerous and rather absurd.

Physics in nature

Of course, nuclear explosions, energy sources, "lawlessness" of computers and lasers, the creation of new materials show that the range of interests of scientists extends far beyond the "fragments of the century before last." However, the caricatured image of a scientist, and indeed of all science, is tenacious. Although few things can be as far from the truth as a picture created by an impressionable and ardent poet. Even when Mayakovsky wrote his verse, dramas of quite Shakespearean proportions played out in and around science. In order to understand me correctly, I note that the question "To be or not to be" as applied to humanity and not to an individual, albeit a very significant one, was first raised precisely thanks to physicists and on the basis of the achievements of physics.

It is not at all accidental that about three centuries have passed under the sign of this science. People involved in it have discovered and are discovering the fundamental laws of nature that determine the structure and movement of material objects in a huge range of distances, times and masses. These ranges are grandiose - from small, atomic and subatomic, to cosmic and universal.

Of course, it was not physicists who said "Let there be light", but it was they who found out its nature and properties, establishing the difference from darkness, and learned how to control them.

In the course of their work, physicists, to a decisive extent the largest of them, have developed a certain style of thinking, the main elements of which are the willingness to rely on well-tested fundamental laws and the ability to single out the main element in a complex natural, and even social, phenomenon, as simple as possible, that makes it possible to understand the complex phenomenon under consideration.

These features of the approach allow physicists to be very successful in dealing with problems that often lie far beyond their narrow specialization.

Confidence in the unity of the laws of nature, based on extensive experimental material, confidence in their validity, combined with a clear understanding of the limited area of ​​applicability of already discovered laws, pushes physics forward, beyond the border of the unknown today.

Physics is a complex science. It requires enormous intellectual effort from the people who deal with it. It is absolutely incompatible with amateurism. I remember how, after graduating from the University and the Shipbuilding Institute in 1958, I stood at a crossroads - where to go next. And my father, very far from science, asked me if I could return to engineering after ten years of physics. My answer was an unqualified yes. "What about physics after ten years of engineering?" he asked. My "no" and determined the further choice, which I did not regret and do not regret for a second.

The complexity of physics and the importance of the results obtained by it, which make it possible to create a picture of the world and stimulate the spread of its ideas far beyond the framework of this science itself, determine public interest To her. Here are some of those ideas, in order. These are scientific (not speculative!) atomism, the discovery of the electromagnetic field, the mechanical theory of heat, the establishment of the relativity of space and time, the concept of an expanding universe, quantum jumps and, in principle, not because of an error, the probabilistic nature of physical processes, first of all, on micro- level, the grand unification of all interactions, the establishment of the existence of not directly observable subatomic particles - quarks.

This is where popular books appear, which are designed not to teach physics to beginners, but to explain it to those who are interested. There is another purpose of popular books, among which the most famous among the people of my generation is " Entertaining physics" Yakov Perelman, not a relative of M.E. Perelman. I mean a demonstration of how much Everyday life, the technique and technology familiar to us, can be qualitatively understood, based only on the already well-known fundamental laws of physics, first of all, the laws of conservation of energy and momentum, and the confidence that they are universally applicable.

There are a great many objects of application of the laws of physics. Why it is not worth pouring water into boiling oil, why the stars twinkle in the sky, why the water swirls, flowing out of the bathroom, why the whip clicks and why the driver spins it over his head to amplify the sound of the click, why steam locomotives once strove to jump off the rails, but never do this electric locomotives? And why does an approaching plane roar menacingly, and, as it moves away, it goes into falsetto, and why do dancers or figure skaters start spinning with their “embraces” wide open, but then quickly press their hands to their bodies? There are a great many such "whys" in everyday, not to mention non-everyday, life. It is useful to learn to see them, to train yourself to search for the incomprehensible.

The books of M. E. Perelman contain a record number of such questions "why?" (more than five hundred), give them answers, in most cases - unambiguously correct, sometimes - inviting discussion, occasionally - most likely incorrect, provoking disagreement. There are also questions to which science today has no simple and generally accepted answer. This means that the reader has room for intensive intellectual work.

Along the way, the author explains what is generally known to professionals, but which causes such a strong bewilderment among outsiders. Namely, the author emphasizes the operational nature of many definitions in such a generally recognized exact science as physics. Professionals know that even the most fundamental of the concepts that physics operates on, such as time and energy, space and momentum, are refined as science itself develops.

Even vacuum, which was once an analogue of absolute emptiness, the absence of anything in the self-evident "empty" space, over time "overgrown" with completely non-trivial features, from the primitive becoming the most difficult object of study. The universality of the physical approach dictates a similar attitude to the definitions of non-trivial concepts in other areas that are very far from physics.

Reading the mentioned books by M.E. Perelman is also interesting for professionals - in order to argue, to find others that allow a simple, sometimes visual, explanation of the issue. Well, a non-specialist will be able to expand his horizons, not necessarily in a hurry to give his own, different from the author's, explanation. It is worth remembering that what is written is a verbal cast, often greatly simplified, from a sometimes very complex physical construction based on a physical theory that is far from simple in the everyday sense of the word. You don't have to follow the lead real character, the director of a Moscow research institute who denied Einstein's private theory of relativity (he did not read the general one!) Because the speed of light is included in the formulas! "And what will happen if the light is turned off?" - the venerable gunsmith wrote to the department of science of the Central Committee of the CPSU.

Studying physics, beginning to understand its laws, you become attached to a special beauty, there is a really additional dimension in the perception of the surrounding world. The great physicist R. Feynman once wrote about this, noting that understanding the nature of the glow of stars, the mechanism of their birth and death makes a picture of the night starry sky even more beautiful and romantic.

In conclusion, I want to note one, somewhat unexpected, aspect of the benefits of knowledge of physics, and by no means superficial. Academician A. B. Migdal once told about him. He sunbathed in the mountains, and a couple settled down nearby. The young man was explaining to his most pleasant companion why the daytime sky is blue. He told her about the scattering of light, mentioned Lord Rayleigh the theorist. The girl was sitting with open mouth, admiringly looking at the erudite. And that carried, and he, showing negligence and inattention to the elders, said that the probability of radiation scattering is proportional to the cube of the frequency.

But Migdal was already alert. Recalling the classic, which is appropriate here only in a very weakened form, to say: perhaps the academician "in his thoughts, under the darkness of the night, kissed the bride's lips." "Young man, the probability of scattering cannot be proportional to the cube of frequency - this would obviously contradict the invariance of the theory with respect to the change in the sign of time. In Rayleigh, as it should be, the probability is not proportional to the cube, but to the fourth power of frequency!", - in his usual tone, not allowing objections, said Migdal. Needless to say, the triangle changed its shape, and the fat-bellied hypotenuse became a leg when it reached the top.

In a word, read about physics, and whoever is not too late - learn it. It will pay off.

Physics in medicine

Medical physics is the science of a system that consists of physical devices and radiation, medical and diagnostic devices and technologies.

The goal of medical physics is to study these systems for the prevention and diagnosis of diseases, as well as the treatment of patients using the methods and means of physics, mathematics and technology. The nature of diseases and the mechanism of recovery in many cases have a biophysical explanation.

Medical physicists are directly involved in the treatment and diagnostic process, combining physical and medical knowledge, sharing responsibility for the patient with the doctor.

The development of medicine and physics have always been closely intertwined. Even in ancient times, medicine used physical factors for medicinal purposes, such as heat, cold, sound, light, various mechanical effects (Hippocrates, Avicenna, etc.).

The first medical physicist was Leonardo da Vinci (five centuries ago), who conducted research on the mechanics of movement of the human body. Medicine and physics began to interact most fruitfully from the end of the 18th - beginning of the 19th centuries, when electricity and electromagnetic waves were discovered, that is, with the advent of the era of electricity.

Let's name a few names of great scientists who made the most important discoveries in different eras.

Late XIX- mid-twentieth century associated with the discovery of x-rays, radioactivity, theories of the structure of the atom, electromagnetic radiation. These discoveries are associated with the names of V.K. Roentgen, A. Becquerel,

M. Skladovskoy-Curie, D. Thomson, M. Planck, N. Bohr, A. Einstein, E. Rutherford. Medical physics really began to establish itself as an independent science and profession only in the second half of the 20th century. with the advent of the atomic age. In medicine, radiodiagnostic gamma devices, electronic and proton accelerators, radiodiagnostic gamma cameras, X-ray computed tomographs and others, hyperthermia and magnetotherapy, laser, ultrasound and other medical-physical technologies and devices have become widely used. Medical physics has many sections and names: medical radiation physics, clinical physics, oncological physics, therapeutic and diagnostic physics.

by the most important event in the field of medical examination can be considered the creation of computed tomography, which expanded the study of almost all organs and systems human body. OCT has been installed in clinics all over the world, and a large number of physicists, engineers and doctors have worked to improve the technique and methods to bring it almost to the limits of what is possible. The development of radionuclide diagnostics is a combination of methods of radiopharmaceutics and physical methods registration of ionizing radiation. Positron emission tomography imaging was invented in 1951 and published in the work of L. Renn.

Physics and Literature

In life, sometimes without noticing it, physics and literature are closely intertwined. Since ancient times, people have used inventions based on the knowledge of physics in order to convey the literary word to their descendants. Little is known about the life of the German inventor Johannes Gutenberg. However, great inventor to bring to us literary masterpieces, he studied the laws of physics and mechanics. In the printing house organized by him, he printed the first books in Europe, which played a huge role in the development of mankind.

The first Russian printer, Ivan Fedorov, was known to his contemporaries as a scientist and inventor. For example, he knew how to cast guns, invented a multi-barreled mortar. And the first wonderful images of literary and printing art - "Apostle" (1564) and "Hourmaker" (1565) will forever remain in people's memory.We call the name of Mikhail Vasilyevich Lomonosov one of the first among the most remarkable representatives of Russian science and culture. A great physicist, he left a number of works of great importance for industrial development Russia. A large place in his scientific works was occupied by optics. He himself made optical instruments and original mirror telescopes. Exploring the sky with his instruments, inspired by the infinity of the Universe, Lomonosov wrote beautiful poems:The abyss of stars is full.The stars have no number, the abyss - the bottom ...

Without such a science as physics, there would be no such literary genre like a science fiction novel. One of the creators of this genre was the French writer Jules Verne (1828 - 1905). Inspired by the great discoveries of the 19th century, the famous writer surrounded physics with a romantic halo. All of his books From the Earth to the Moon (1865), Captain Grant's Children (1867-68), 20,000 Leagues Under the Sea (1869-70), Mysterious Island"(1875) are imbued with the romance of this science.

In turn, many inventors and designers were inspired by the incredible adventures of the heroes of Jules Verne. So, for example, the Swiss scientist-physicist Auguste Piccard, as if repeating the paths of fantastic heroes, climbed into the stratosphere on the stratosphere balloon he invented, taking the first step towards uncovering the secret of cosmic rays. O. Piccard's next passion was the idea of ​​conquering sea ​​depths. The inventor himself sank to the seabed, on the bathyscaphe he built (1948).

About 160 years ago, in the journal Otechestvennye Zapiski, Letters on the Study of Nature (1844-1845) by A. I. Herzen were published - one of the most significant and original works in the history of both philosophical and natural sciences of Russia thoughts. The revolutionary, philosopher, author of one of the masterpieces of Russian classical literature, The Past and Thoughts, Herzen, nevertheless, was keenly interested in the natural sciences, including physics, which he repeatedly emphasized in his writings.

Now it is necessary to turn to the literary heritage of Leo Tolstoy. Firstly, because the great writer was a teacher-practitioner, and secondly, that many of his works concern natural sciences. The most famous comedy is The Fruits of Enlightenment. The writer was extremely negative about "any superstitions", he believed that they "hinder the true teaching and prevent it from penetrating into the soul of people." Tolstoy understood the role of science in the life of society in this way: firstly, he was a supporter of organizing the life of society on a strict scientific basis; secondly, he makes a strong emphasis on moral and ethical norms, and because of this, the natural sciences in Tolstoy's interpretation turn out to be secondary sciences. That is why Tolstoy in Fruits of Enlightenment ridicules the Moscow nobility, in whose heads science and anti-science are mixed.

It must be said that at the time of Tolstoy, on the one hand, the then physics was going through a severe crisis in connection with the experimental verification of the basic provisions of the theory of the electromagnetic field, which refuted Maxwell's hypothesis about the existence of the world ether, that is, the physical medium that transmits the electromagnetic interaction; and on the other hand there was a craze for spiritualism. In his comedy, Tolstoy describes the scene of a séance, where the natural science aspect is clearly visible. Particularly indicative is Professor Krugosvetlov's lecture, where an attempt is made to give a scientific interpretation of mediumistic phenomena.

If we talk about the modern significance of Tolstoy's comedy, then perhaps the following should be noted:

1. When for some reason, this or that phenomenon of nature does not receive a timely explanation, then its pseudo-scientific, and sometimes anti-scientific interpretation is a very common thing.

2. The very fact that the writer considers scientific topics in a work of art is significant.

Later, in the final chapter of the treatise "What is art?" (1897) Lev Nikolaevich emphasizes the relationship between science and art, as two forms of knowledge of the world around, taking into account, of course, the specifics of each of these forms. Cognition through the mind in one case and through the senses in the other.

Apparently, it was no coincidence that the great famous American inventor Thomas Alva Edison (1847 - 1931) sent one of his first phonographs to L. N. Tolstoy, and thanks to this, the voice of the great Russian writer was preserved for posterity.

The Russian scientist Pavel Lvovich Schilling was destined to go down in history thanks to his work in the field of electricity. However, one of Schilling's main hobbies - oriental studies - made his name widely known. The scientist collected a huge collection of Tibetan-Mongolian literary monuments, the value of which is difficult to exaggerate. For which, in 1828, P. L. Schilling was elected a corresponding member of the St. Petersburg Academy of Sciences in the category of literature and antiquities of the East.

It is impossible to imagine world literature without poetry. Physics in poetry occupies a worthy role allotted to it. Poetic images, inspired by physical phenomena, give visibility and objectivity to the world of thoughts and feelings of poets. What kind of writers did not turn to physical phenomena, perhaps even themselves, without knowing it, described them. For any physicist, the phrase "I love a thunderstorm in early May ..." will evoke associations with electricity.

The transmission of sound was described by many poets in different ways, but always ingeniously. So, for example, A. S. Pushkin in his poem "Echo" perfectly describes this phenomenon:Does the beast roar in the deaf forest,Does the horn blow, does the thunder rumble,Does the maiden sing beyond the hill -For every soundYour response in the empty airYou suddenly give birth.

G. R. Derzhavin’s “Echo” looks a little different:But, suddenly, receding from the hillReturning thunder,Thunders and surprises the world:Thus forever the echo of the lyre is immortal.

Almost all poets also turned to the theme of sound, singing and invariably admiring its transmission over a distance.

In addition, almost all physical phenomena inspired creative people. It is difficult to find such a poet in world literature who would not at least once write works about the earth and sky, about the sun and stars, about thunder and lightning, about comets and eclipses:And, like any comet,Embarrassing with the brilliance of novelty,You rush like a dead lump of lightA path devoid of straightness!(K. K. Sluchevsky)You learn from the sky and follow it:Itself is in motion, but the pole is motionless.(Ibn Hamdis)

Our parents also remember the dispute that flared up at the turn of the 60s - 70s between "physicists" and "lyricists". Everyone tried to find priorities in their own science. There were no winners or losers in that dispute, and there could not be, since it is impossible to compare two forms of cognition of the surrounding world.

I would like to end with an excerpt from the work of Robert Rozhdestvensky (the famous member of the sixties), dedicated to nuclear physicists. The work is called "People whose names I do not know":How many different things would you come up with!Much needed and amazing!You know that for the mindNo boundaries are foreseen.How easy it would be for people to breathe!How would people love light!And what thoughts would beatin the hemispheresthe globe!..But so far blows over the worldA little softening disbelief.But while the diplomats are tallCompose messages soft, -For the time being, and yetYou remain nameless.Nameless. Unsociable.Ingenious invisible...Every student in the world to comeYour life will boast ...Low - low bow to you, people.You Great Ones.

No last names.

Physics and art

art keeps the richest opportunities for aesthetic education in the process of teaching physics. Often, students capable of painting are burdened by lessons in which the exact sciences are taught to them in the form of a set of laws and formulas. The teacher's task is to show that people of creative professions simply need knowledge of physics professionally, because "... an artist who does not have a certain worldview has nothing to do in art now - his works, wandering around the particulars of life, will not interest anyone and will die before they were born" . In addition, very often an interest in a subject begins precisely with an interest in a teacher, and the teacher must know at least the basics of painting and be an artistically educated person, so that living ties are born between him and his students.

This information can be used in different ways: to illustrate physical phenomena and events from the life of physicists with works of art, or, conversely, to consider physical phenomena in the technique of painting and the technology of painting materials, to emphasize the use of science in the arts, or to describe the role of color in production. But at the same time, it must be remembered that painting in a physics lesson is not a goal, but only an assistant, that any example should be subordinated to the internal logic of the lesson, in no case should one stray into an artistic and art history analysis.

The student meets art already at the first lessons of physics. So he opens the textbook, sees a portrait of M.V. Lomonosov and recalls the words of A.S. Pushkin, familiar from literature lessons, that Lomonosov “was our first university himself.” Here you can talk about the scientist's experiments with colored glass, show his mosaic panel "The Battle of Poltava" and sketches of the aurora borealis, read his poetic lines about science, about the joy that comes with acquiring new knowledge, outline the scope of the scientist's interests as a physicist, chemist, artist , a writer, quote the words of Academician I. Artobolevsky: “Art for a scientist is not a rest from intense studies in science, not only a way to rise to the heights of culture, but an absolutely necessary component of his professional activity.”

Particularly advantageous in this regard is the "Optics" section: linear perspective (geometric optics), aerial perspective effects (diffraction and diffuse scattering of light in air), color (dispersion, physiological perception, mixing, complementary colors). It is useful to look into painting textbooks. It reveals the meaning of such characteristics of light as luminous intensity, illumination, angle of incidence of rays. Talking about the development of views on the nature of light, the teacher talks about the ideas of ancient scientists, that they explained light as the outflow of the thinnest layers of atoms from bodies with the greatest speed: “These atoms compress the air and form imprints of images of objects reflected in the moist part of the eye. Water is the medium of vision, and therefore a wet eye sees better than a dry one. But air is the reason why distant objects are not clearly visible.

Various sensations of light and color can be described when studying the eye, consider the physical basis optical illusions, the most common of which is the rainbow.

I. Newton was the first to understand the "device" of the rainbow, he showed that the "sunbeam" consists of various colors. Very impressive is the repetition in the class of the experiments of the great scientist, while it is good to quote his treatise "Optics": "The spectacle of the lively and bright colors that resulted from this gave me pleasant pleasure."

Later, the physicist and talented musician Thomas Jung would show that the differences in color are due to different wavelengths. Jung is one of the authors of modern color theory along with G. Helmholtz and J. Maxwell. The priority in creating a three-component theory of colors (red, blue, green - the main ones) belongs to M.V. Lomonosov, although the famous Renaissance architect Leon Batista Alberti also expressed a brilliant guess.

In confirmation of the enormous influence on the impression of the power of color, one can cite the words of the famous specialist in technical aesthetics, Jacques Vienot: “Color is capable of everything: it can give birth to light, calm or excitement. It can create harmony or cause shock: miracles can be expected from it, but it can also cause disaster. It should be mentioned that the properties of color can be given "physical" characteristics: warm (red, orange) - cold (blue, blue); light (light colors) - heavy (dark). Color can be "balanced".

A good illustration of the physiological perception of mixing colors can be the painting by V.I. Surikov “Boyar Morozova”: the snow on it is not just white, it is heavenly. On closer examination, you can see a lot of colored strokes, which from afar, merging together, and create the right impression. This effect also fascinated the Impressionist artists, who created a new style - pointillism - painting with dots or strokes in the form of commas. "Optical mixture" - a decisive factor in the technique of execution, for example, J.P. Seurat, allowed him to achieve extraordinary transparency and "vibration" of the air. Students know the result of mechanical mixing yellow + blue = green, but they are invariably surprised at the effect that occurs when smears of additional colors, such as green and orange, are applied next to the canvas - each of the colors becomes brighter, which is explained hard work retinas of the eye.

Many illustrations can be found on the laws of reflection and refraction of light. For example, an image of an overturned landscape on a calm surface of water, a mirror with the replacement of the right for the left and the preservation of size, shape, color. Sometimes an artist introduces a mirror into a painting with a dual purpose. So, I. Golitsyn in the engraving depicting V. A. Favorsky, firstly, shows the face of the old master, whose entire figure is turned back to us, and secondly, he emphasizes that the mirror here is also a tool for work. The fact is that an etching or engraving on wood or linoleum is cut in a mirror image so that the print is normal. In the process of work, the master checks the image on the board by reflection in the mirror.

The well-known popularizer of science, physicist M. Gardner, in his book “Painting, Music and Poetry” noted: “Reflection symmetry is one of the oldest and easiest ways to create images that please the eye.”

Conclusion

So, we are convinced that physics surrounds us everywhere and everywhere.

Bibliography:

    Great Soviet Encyclopedia.

    Internet encyclopedia "Wikipedia"

municipal budgetary educational institution

"Average comprehensive school№92"

Research

Physics around us

Work completed:

Queen V.S.,

MBOU "Secondary School No. 92", 8a class

Supervisor:

Prokopenko O.I.,

physics and mathematics.

Novokuznetsk, 2016

Introduction……………………………………………………………………………3

    The use of physics in everyday life……………………………………………………….4

    The use of physics in medicine………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………….

    Application of physics to biology………………………………………………………8

    Application of physics in music…………………………………………………………………………………………………. ten

    Conclusion……………………………………………………………………..............13

    References…………………………………………………………….16

Introduction

Purpose: to study the application of physics in various fields.
Tasks: to explore the application of the laws of physics:
1. at home

2. in medicine

3. in biology

4. in music

Physics surrounds us everywhere, especially at home. We are used to not seeing it.

Knowledge of physical phenomena and laws helps us in household chores, protects us from mistakes.

Look at what is happening in your home through the eyes of a physicist, and you will see a lot of interesting and useful things!

In this paper, we consider the application of physics in

    medicine

    biology

Knowing the following laws of physics helps us explain various phenomena:

    condensation (formation of liquid droplets in the bath);

    diffusion (brewing tea, pickling cucumbers, spreading the smell);

    heat transfer (convection when heating a room with batteries, thermal conductivity when insulating houses);

In everyday life, we use various devices, their action is also based on the laws of physics. Not all devices are safe to use, for example, you can’t talk on a mobile phone for a long time, as electromagnetic waves will affect the brain.

In the section of physics in medicine, the use of sound, ultrasound, electromagnetic waves for human health is considered.

In the section on physics in biology, the influence of the invention of the microscope on the development of biology is considered.

The application of physics to music section discusses the application of the laws of physics to amplify sound.

This work is aimed at drawing attention to the science of "Physics", the study of the laws of physics, since knowledge of the laws of physics is necessary in our life.

The use of physics in everyday life

In the section on the application of physics in everyday life, the application of the laws of physics in the kitchen, in the bathroom, in everyday life is considered.

Knowing the following laws of physics helps us explain various phenomena.

    Thermal phenomena in the kitchen.

To cool hot tea, we use that the rate of evaporation of the liquid depends on:

    from the surface area (pouring tea into a saucer)

    from the wind (we blow)

    from the kind of liquid

    on the temperature of the liquid.

An example of using the difference in thermal conductivity:

“So that a glass cup does not burst when boiling water is poured into it,

put a metal spoon "The metal spoon serves to equalize the temperature difference and helps to cup heated evenly and not burst.

    Condensation (formation of droplets of liquid in the bath). A cold water faucet can always be distinguished by the water droplets that have formed on it.

when water vapor condenses.

    Diffusion (brewing tea, pickling cucumbers, spreading the smell);

    Heat transfer (convection when heating a room with batteries, thermal conductivity when insulating houses). The handles of the pots are made of materials that conduct heat poorly so as not to get burned. There is air in the double-glazed windows between the glasses

(sometimes it is even pumped out). Its poor thermal conductivity hinders heat transfer

between cold air outside and warm air in the room. In addition, double-glazed windows reduce noise levels.

Batteries in apartments are located below, since the hot air from them rises as a result of convection and heats the room.

    pressure (grinding knives to increase pressure);

    lever properties (scissors, scales);

    communicating vessels (kettle, fountain);

    friction force (methods of increasing the friction force on ice and decreasing it when skating);

    electrification (when combing).

    The devices that we often use in everyday life also work based on the laws of physics. (Watch, barometer, tonometer, iron, vacuum cleaner, mobile phone.

Application of physics in medicine

Physics in medicine plays a huge role, it is also called biophysics, and even better biomedical physics, all the basic laws of physics are easily applicable to living things.

Ultrasound is a high-frequency mechanical vibration of particles of a solid, liquid or gaseous medium, inaudible to the human ear. The frequency of ultrasound oscillations is above 20,000 per second, i.e., above the threshold of hearing.

For therapeutic purposes, ultrasound is used with a frequency of 800,000 to 3,000,000 vibrations per second. Devices called ultrasonic transducers are used to generate ultrasound.

Most widespread received electromechanical emitters. The use of ultrasound in medicine is associated with the peculiarities of its distribution and characteristic properties. By physical nature, ultrasound, like sound, is a mechanical (elastic) wave. However, the wavelength of ultrasound is much smaller than the wavelength of the sound wave. The greater the various acoustic impedances, the stronger the reflection and refraction of ultrasound at the boundary of dissimilar media. The reflection of ultrasonic waves depends on the angle of incidence on the affected area - the larger the angle of incidence, the greater the reflection coefficient.

In the body, ultrasound with a frequency of 800-1000 kHz propagates to a depth of 8-10 cm, and at a frequency of 2500-3000 Hz - by 1.0-3.0 cm. Ultrasound is absorbed by tissues unevenly: the higher the acoustic density, the lower the absorption.

Three factors act on the human body during ultrasound therapy:

1) mechanical - vibration micromassage of cells and tissues;

2) thermal - an increase in the temperature of tissues and the permeability of cell membranes;

3) physical and chemical - stimulation of tissue metabolism and regeneration processes.

The biological effect of ultrasound depends on its dose, which can be stimulating, depressing or even destructive for tissues. The most adequate for therapeutic and prophylactic effects are small dosages of ultrasound (up to 1.2 W/cm2), especially in a pulsed mode. They are able to provide analgesic, antiseptic (antimicrobial), vasodilating, resolving, anti-inflammatory, desensitizing (antiallergic) action.

Ultrasound is not applied to the area of ​​the brain, cervical vertebrae, bony prominences, areas of growing bones, tissues with severe circulatory disorders, to the abdomen during pregnancy, the scrotum. With caution, ultrasound is used on the region of the heart, endocrine organs.

The use of ultrasound for diagnosis.

Ultrasonic vibrations during propagation obey the laws

geometric optics. In a homogeneous medium, they propagate in a straight line and

at a constant speed. At the boundary of different media with unequal acoustic

density part of the rays is reflected, and part is refracted, continuing

rectilinear distribution. The higher the acoustic drop gradient

density of boundary media, the greater part of ultrasonic vibrations

reflected. Since at the border of the transition of ultrasound from the air to the skin

99.99% of the vibrations are reflected, then with ultrasound scanning

the patient needs lubrication of the skin surface with water jelly, which

acts as a transitional medium. Reflection depends on the angle of incidence of the beam

(the largest in the perpendicular direction) and ultrasonic frequencies

oscillations (at a higher frequency, most of it is reflected).

For the study of the abdominal cavity and retroperitoneal space, as well as

the pelvic cavity uses a frequency of 2.5 - 3.5 MHz, for research

thyroid uses a frequency of 7.5 MHz.

The ultrasonic wave generator is a piezoelectric transducer, which simultaneously

plays the role of a receiver of reflected echoes. The generator operates in a pulsed

mode, sending about 1000 pulses per second. Between

By generating ultrasonic waves, the piezoelectric transducer captures the reflected signals.

The use of ultrasound in surgery.

There are two main applications of ultrasound in surgery. The first of them uses the ability of a highly focused ultrasound beam to cause local destruction in tissues, and in the second, mechanical vibrations of ultrasonic frequency are superimposed on surgical instruments such as blades, saws, mechanical tips.

Surgery with focused ultrasound.

Surgical technique should ensure controllability of tissue destruction, affect only a clearly defined area, be fast-acting, and cause minimal blood loss. Powerful focused ultrasound has most of these qualities.

Ability to use focused ultrasound to create zones

lesions in the depths of the organ without destruction of the overlying tissues were studied in

mostly in brain surgery. Later operations were performed on the liver, spinal cord, kidneys and eye.

Application of physics in biology

The revolution in biology is usually associated with the emergence of molecular biology and genetics, which study life processes at the molecular level. The main tools and methods used by molecular biology to detect, isolate and study its objects (electron and proton microscopes, x-ray diffraction analysis, electron diffraction, neutron analysis, labeled atoms, ultracentrifuges, etc.) are borrowed from physics. Without these tools, which were born in physical laboratories, biologists would not be able to make a breakthrough in the qualitative new level studies of processes occurring in living organisms.

The widespread introduction of physical methods of research into biology has made it possible to study biological phenomena at the molecular level. The brilliant work of biochemists, physiologists, biophysicists and crystallographers established the molecular structures of a number of important biological objects. For example, the structure of deoxyribonucleic acid (DNA) - the main carrier of hereditary information, the structure of myoglobin molecules that store oxygen in the muscles of animals, the structure of hemoglobin molecules that make up red blood cells and carry oxygen from the lungs to tissues, the structure of striated muscles and protein molecules, included in their composition, the structure of some enzymes, vitamins and a number of other important biological molecules.

New experimental data obtained in the study of biological processes at the molecular level have put the question of their interpretation on the agenda. Since all living organisms are built from molecules and atoms, elucidation at the molecular level of the mechanism of bioprocesses is possible only with the help of quantum theory, which successfully describes the movement of electrons and nuclei that make up molecules and atoms.

The close connection between biology and physics was manifested already at the early stages of the development of natural science. However, along with materialistic understanding Between physics and biology for a long time there was a deeply erroneous, anti-scientific point of view, called "vitalism". Vitalists argued that the living is allegedly separated from the non-living by an impenetrable abyss and is subject to no natural patterns, a " vitality and therefore incomprehensible to man.

Application of physics in music

Man lives in the world of sounds. Sound is what the ear hears. We hear the voices of people, the singing of birds, the sounds of musical instruments, the noise of the forest, thunder during a thunderstorm. When we hear a sound, we can usually establish that it has come down to us from some source. Looking at this source, we will always find something vacillating in it. If, for example, sound comes from a loudspeaker, then a membrane vibrates in it - a light disk fixed around its circumference. If a sound is produced by a musical instrument, then the source of the sound is a vibrating string, a vibrating column of air, etc.

But how does sound reach us? Obviously through the air that separates the ear and the sound source. But the propagating vibrations are a wave. Therefore, sound travels in the form of waves. If a sound wave propagates in air, then it is a longitudinal wave, because only such waves are possible in a gas.

In longitudinal waves, oscillations of particles lead to the fact that in the gas there are regions of condensation and rarefaction replacing each other. The fact that air is a "conductor" of sound was proved by an experiment set in 1660 by R. Boyle. If the air is pumped out from under the bell of the air pump, then we will not hear the sound of the electric bell located there.

Sound can also propagate in both liquid and solid media.

The sensation of sound is created only at certain frequencies of vibration in the wave. Experience shows that for the human hearing organ, sound waves are only those in which vibrations occur with frequencies from 20 to 20,000 Hz. The lowest musical sound audible to man has a frequency of 16 vibrations per second. It is extracted by the body. But it is not used often - it is very bass. It is difficult to disassemble and understand it. But 27 vibrations per second - a tone quite clear to the ear, although also rare. You can hear it by pressing the leftmost piano key. The absolute "lower" record for a male bass, set in the 18th century by the singer Kaspar Fesper, is 44 vibrations per second. 80 beats per second is a common bottom note for good bass and many instruments. By doubling the number of oscillations (raising the sound by an octave), we arrive at a tone accessible to cellos and violas. Basses, baritones, tenors, and female contraltos feel great here. And another octave up - and we find ourselves in that part of the range where almost all voices and musical instruments work. No wonder it was in this area that acoustics fixed the universal standard of pitch: 440 vibrations per second ("la" of the first octave). Up to 1000-1200 vibrations per second, the sound range is full of music. These sounds are the most audible. Above are the less populated "floors". Only violins, flutes, organ, piano, harp climb them easily. And sonorous sopranos act as sovereign mistresses. The peaks of the female voice climbed even further. In the XVIII century, Mozart admired the singer Lucrezia Ajuyari, who took "to" the fourth octave - 2018 vibrations per second. The Frenchwoman Mado Robin (who died in 1960) sang in a full voice "re" of the fourth octave - 2300 vibrations per second.

A few more rare, untrodden steps (only accessible to masters of artistic whistling) - and the musical range ends. Sounds above 2500-3000 vibrations per second are not used as independent musical tones. They are too sharp, piercing.

There are special sources of sound that emit a single frequency, the so-called pure tone. These are tuning forks of various sizes - simple devices that are curved metal rods on legs. The larger the tuning forks, the lower the sound it emits when struck.

Sounds of even the same tone can be of different loudness. This characteristic of sound is related to the energy of oscillations in the source and in the wave. The energy of oscillations is determined by the amplitude of oscillations. The loudness, therefore, depends on the amplitude of the vibrations. But the relationship between loudness and amplitude is not simple.

The weakest sound still audible, reaching the eardrum, brings in 1s. an energy equal to about 10 -16 J, and the loudest sound (of a jet rocket engine a few meters away) is about 10 -4 J. Therefore, the loudest sound is about a thousand billion times more powerful than the weakest. But the same cannot be said about the volume of the sound. It is impossible to say about sounds in general that one of them is two, three, and even more so millions or billions of times louder than the other. They say about sounds of different loudness that one is louder than the other not by so many times, but by so many units. The unit of loudness is called decibel (dB). For example, the volume of the sound of the rustle of leaves is estimated at 10 dB, whisper - 20 dB, street noise - 70 dB. Noise with a volume of 130 dB is felt by the skin and causes a sensation of pain. About the volume of street noise, for example, we can say that it is 60 dB more than the rustle of leaves.

Sound vibrations carried by a sound wave can serve as a driving, periodically changing force for oscillatory systems and cause a resonance phenomenon in these systems, i.e. make them sound. This resonance is called acoustic resonance. For example, a device for obtaining a pure tone, i.e. sound of one frequency, the tuning fork itself gives a very weak sound, because the surface area of ​​the oscillating branches of the tuning fork in contact with air is small and too few air particles come into the oscillatory motion. Therefore, the tuning fork is usually mounted on a wooden box, selected so that the frequency of its natural oscillations is equal to the frequency of the sound produced by the tuning fork. Due to resonance, the walls of the box also begin to oscillate at the frequency of the tuning fork. These are oscillations of large amplitude (resonance!), and the surface area of ​​the box is large, so the sound of the tuning fork is much louder. The box is called the resonator. In musical instruments, resonators are also indispensable. They serve as decks. Without them, from strings alone, the sounds would be almost inaudible. The human oral cavity is also a resonator for the vocal cords.

TOTAL
1. Musical sounds are the result of rapid, regular vibrations of bodies.
2. The pitch of a sound is measured by the frequency of the sound waves.
3. Sound waves can be made visible using a cathode oscilloscope.

Conclusion

Where is physics used?

Physics is the science of nature (natural science) in the most general sense (part natural history). The subject of her study is matter(as substances and fields) and the most general forms of its movement, as well as fundamental interactions nature that governs the motion of matter.

Some patterns are common to all material systems, For example, energy saving They are called physical laws. Physics is sometimes called "basic science" because others natural Sciences (biology, geology, chemistry etc.) describe only a certain class of material systems that obey the laws of physics. For example, chemistry studies atoms formed from them substances and the transformation of one substance into another. The chemical properties of a substance are uniquely determined physical properties atoms and molecules described in such branches of physics as thermodynamics, electromagnetism and the quantum physics .

Physics is closely related to mathematics: Mathematics provides the apparatus by which physical laws can be precisely stated. Physical theories almost always formulated as mathematical expressions, using more complex branches of mathematics than is usual in other sciences. Conversely, the development of many areas of mathematics was stimulated by the needs of physical theories. As you and I learned, physics is used in different directions, whether it is medicine, or biology, or everyday life, or music.

Analysis of survey results

A survey was conducted for grades 7-9 on the following questions:

1. What physical phenomena do you notice in everyday life?

2. Have you ever used knowledge of physics in everyday life?

3. Have you ever been in unpleasant everyday situations:
Burning with steam or hot parts of dishes

electric shock

Short circuit

The device was plugged into the outlet, and it burned out

4. Could your knowledge of physics help you avoid unpleasant situations?

5. Are you interested in buying household appliances them:

Specifications
safety
operating rules
possible negative health effects

6. Do you think physics is related to music?

7. Are physics related to medicine?

8. Are physics related to biology?

Test analysis

    When studying physics at school, more attention should be paid to questions practical application physical knowledge in everyday life.

    At school, students should be introduced to the physical phenomena that underlie the operation of household appliances. Special attention focus on the possible negative impact household appliances on the human body.

    In physics lessons, students should be taught how to use instructions for electrical appliances.

    Before allowing a child to use a household electrical appliance, adults should make sure that the child has firmly mastered the safety rules for handling it.

Bibliography

    Gorev L.A. Entertaining experiments in physics - grades 6-7. 1985.

    Detlaf A.A., Yavorsky B.M. Course of general physics. - M.: Higher school, 1989

    Irodov I.E. Electromagnetism. Basic laws. - M.: Basic Knowledge Laboratory, 2001.

    Kalashnikov S.G. Electricity. - M.: Nauka, 2005.

    Kitel I., Knight W., Ruderman M. Berkeley Physics Course. Mechanics. - M.: Nauka, 2003.

    Kovtunovich M.G.. Home experiment in physics, grades 7-11, 2007.

    Purcell E. Berkeley Physics Course. electricity and magnetism. - M.: Nauka, 1983.

Physics is a school subject, in the study of which many people face problems. From the course of physical knowledge, many have learned only a quote from Archimedes: “Give me a fulcrum, and I will turn the world upside down!”. In fact, physics surrounds us at every step, and physical life hacks make life easier and more convenient. Meet another dozen life hacks that will expand your horizon of knowledge about the world around you.

1. Puddle, disappear!

If you spill water, do not rush to wipe up the puddle. Just rub it on the floor, increasing the surface area of ​​the liquid. The larger the surface of the liquid, the faster it will evaporate. Of course, “sweet” puddles are not left to dry out: the water will evaporate, and the sugar will remain.

2. Shadow tan


Direct Sun rays and sensitive skin - dubious tandem. To "gold" the body and not get burned, sunbathe in the shade. Ultraviolet radiation is scattered everywhere and will "reach" you even under palm trees. Do not refuse dates with the sun, but protect yourself from its burning kisses.

3. Automatic watering of plants


Going on vacation? Take care of potted plants. Organize automatic watering: place a jar of water next to the pot, lower a cotton cord into it to the bottom, put the other end into the pot. The capillary effect works. Water fills the voids in the fabric fibers and moves through the fabric. The system works by itself - as the earth dries up, the movement of water through the fabric increases and, conversely, with sufficient moisture, it stops.

4. Quickly cool the drink


To quickly cool your drink bottle, wrap it in a damp paper towel and place it in the freezer. It is known that water evaporates from a wet surface, and the temperature of the remaining liquid decreases. Evaporative cooling effect will enhance the cooling effect freezer, and the wet bottle will cool much faster.

5. Properly cool food


Another physical hack on the topic of proper cooling is dedicated to products. Cold air always goes down, warm air always goes up. And that is why refrigerants in the freezer bag should be placed on top! Otherwise, cold air remains from below, and the upper products will be spoiled.

6. sunlight flask from a bottle


Attic spaces also need lighting. If there is no way to conduct lamp light, use solar energy. Make a hole in the roof of the attic and fix a plastic water bottle in it. Sunlight, reflected and scattered, evenly illuminates the room. Alas, such a "lamp" works only during the day.

7. Milk won't run away


How to boil milk so that it does not run away, and the stove does not have to be tediously scrubbed? Put a saucer upside down on the bottom of the pan, pour milk. The saucer will hold back the foaming and simmering, forcing the milk to boil like water.

8. Boil Potatoes Quickly


If you put butter in the water when boiling potatoes, the heat capacity of the water will increase, and the potatoes will cook 2 times faster! In addition, butter will have the most positive effect on the taste of potatoes.

9. "Cure" for a foggy mirror


The misted mirror in the bathroom breaks the harmonious rhythm of the gathering. How to get rid of condensation? When taking a shower, the air heats up, but the surface of the mirror remains cold. To solve the problem, it is enough to smooth out the temperature difference - for example, warm the mirror with a hairdryer.

10. Cool handle


Some materials heat up quickly - iron, copper, silver and other metals. Others receive and transfer heat slowly - cork, wood or ceramics. So upgrade your heated handles by threading wooden wine bottle corks into the ears.

Attention! The administration of the site rosuchebnik.ru is not responsible for the content of methodological developments, as well as for the compliance of the development with the Federal State Educational Standard.

  • Participant: Fedaeva Anna Vladimirovna
  • Head: Gusarova Irina Viktorovna
Goals and objectives of this work:

1) Find out how physics affects human life and whether a modern person can live without its use;

2) Show the need for physical knowledge for everyday life and self-knowledge;

3) Analyze how much a person is interested in physics in the 21st century.

Introduction

Man, as the highest value of our civilization, is studied by a number of scientific disciplines: biology, anthropology, psychology and others. However, the creation of a holistic view of the human phenomenon is impossible without physics. Physics is the leader modern natural science and the foundation of scientific and technological progress, and there are enough reasons for this. Physics, to a greater extent than any of the natural sciences, has expanded the boundaries of human knowledge. Physics has placed in the hands of man the most powerful sources of energy, which has sharply increased man's power over nature. Physics is now the theoretical foundation of most of the main areas of technological progress and areas of practical use of technical knowledge. Physics, its phenomena and laws operate in the living world and inanimate nature, which is very important for the life and activity of the human body and the creation of natural optimal conditions for the existence of man on Earth. Man is an element physical world nature. It, like all objects of nature, is subject to the laws of physics, for example, Newton's laws, the law of conservation and transformation of energy, and others. Therefore, in my opinion, this topic is extremely relevant for modern man.

Rationale for project selection: every day, without noticing it, we come into contact with physics. It became interesting to me how and where we come into contact with physics at home or on the street.

Goals and objectives of my work:

  1. Find out how physics affects a person's life and whether a modern person can live without its use.
  2. Show the need for physical knowledge for everyday life and self-knowledge
  3. Analyze how much a person is interested in physics in the 21st century.

Centripetal force

Here is a boy spinning a stone on a rope. He spins this stone faster and faster until the rope breaks. Then the stone will fly somewhere to the side. What force broke the rope? After all, she was holding a stone, the weight of which, of course, did not change. The centrifugal force acts on the rope, scientists answered even before Newton.

Long before Newton, scientists figured out that in order for a body to rotate, a force must act on it. But this is especially clear from Newton's laws. Newton was the first scientist to systematize scientific discoveries. He established the cause of the rotational motion of the planets around the Sun. The force causing this movement was the force of gravity.

Since the stone moves in a circle, it means that a force acts on it, changing its movement. After all, by inertia, the stone should move in a straight line. This important part of the first law of motion is sometimes forgotten.

The movement by inertia is always rectilinear. And the stone that breaks the rope will also fly in a straight line. The force that corrects the path of the stone acts on it all the time while it rotates. This constant force is called the centripetal layer. It is attached to the stone.

But then, according to Newton's third law, there should be a force acting from the side of the stone on the rope and equal to the centripetal. This force is called centrifugal. The faster the stone rotates, the greater the force must act on it from the side of the rope. And, of course, the stronger the stone will pull - to tear the rope. Finally, its margin of safety may not be enough, the rope will break, and the stone will fly by inertia now in a straight line. Since he maintains his speed, he can fly very far.

Manifestation and application

If you have an umbrella, you can turn it upside down on the floor and put in it, for example, a piece of paper or newspaper. Then spin the umbrella hard.

You will be surprised, but the umbrella will throw out your paper projectile, moving it from the center to the edge of the rim, and then completely out. The same will happen if you place a heavier object, such as a baby ball.

The force that you observed in this experiment is called centrifugal force. This force is a consequence of a more global law of inertia. Therefore, the objects participating in the rotational movement, striving according to this law to maintain the direction and speed of their original state, seem to “have no time” to move around the circle and therefore begin to “fall out” and move towards the edge of the circle.

We encounter centrifugal force almost constantly in our lives. Which we don't even suspect. You can take a stone and tie it to a rope and start spinning. You will immediately feel how the rope is stretched, and tend to break under the action of centrifugal force. The same force helps a cyclist or a motorcyclist in a circus to describe the "dead loop". Honey is extracted from the combs by centrifugal force and clothes are dried in washing machine. And the rails for sharp turns of trains and trams, precisely because of the centrifugal effect, make the "internal" lower than the "outer".

Lever arm

Everyone who has studied physics knows the saying of the famous Greek scientist Archimedes: "Give me a point of support, and I will move the Earth." It may seem somewhat self-confident, nevertheless, he had grounds for such a statement. After all, if you believe the legend, Archimedes exclaimed so, for the first time describing from the point of view of mathematics the principle of operation of one of the oldest lever mechanisms. When and where this elementary device, the foundation of all mechanics and technology, was first used, it is impossible to establish. Obviously, even in ancient times, people noticed that it is easier to break off a branch from a tree if you press on its end, and a stick will help lift a heavy stone from the ground if you pry it from below. Moreover, the longer the stick, the easier it is to move the stone from its place. Both a branch and a stick are the simplest examples of the use of a lever; people intuitively understood the principle of its operation even in prehistoric times. Most of the oldest tools of labor - a hoe, an oar, a hammer with a handle, and others - are based on the application of this principle. The simplest lever is a crossbar that has a fulcrum and the ability to rotate around it. A swinging board lying on a round base is the most good example. The sides of the crossbar from the edges to the fulcrum are called the arms of the lever.

Domenico Fetti. Thinking Archimedes. 1620 Already in the 5th millennium BC. e. in Mesopotamia, they used the principle of leverage to create equilibrium scales. Ancient mechanics noticed that if you set a fulcrum exactly under the middle of a swinging plank, and put weights on its edges, the edge on which the heavier load lies will go down. If the weights are the same in weight, the plank will take a horizontal position. Thus, it was experimentally found that the lever will come into balance if equal efforts are applied to its equal arms. But what if you shift the fulcrum, making one shoulder longer and the other short? This is exactly what happens if a long stick is slipped under a heavy stone. The earth becomes the fulcrum, the stone presses on the short arm of the lever, and the man on the long one. And here are the miracles! a heavy stone, which cannot be torn off the ground with hands, rises. This means that in order to balance a lever with different arms, it is necessary to apply different efforts to its edges: more force to the short arm, less to the long one. This principle was used by the ancient Romans to create another measuring instrument, the steelyard. Unlike balance scales, the steelyard arms were of different lengths, and one of them could be lengthened. The heavier the load had to be weighed, the longer the sliding arm was made, on which the weight was hung. Of course, the measurement of weight was only a special case of using a lever. Much more important were the mechanisms that facilitate labor and make it possible to perform such actions for which the physical strength of a person is clearly not enough. The famous Egyptian pyramids to this day remain the most grandiose structures on Earth. Until now, some scientists express doubt that the ancient Egyptians were able to build them on their own. Pyramids were built from blocks weighing about 2.5 tons, which had to be not only moved along the ground, but also lifted up.

Static electricity

All of us experience static electricity. For example, you probably noticed that after a long combing, your hair begins to “stick out” in different directions. Or, during the removal of clothes in the dark, small numerous discharges are observed.

If we consider this effect from the physical side, then this phenomenon is characterized by the loss of the internal balance of the subject, which is caused by the loss (or acquisition) of one of the electrons. Simply put, it is a spontaneously generated electric charge arising from the friction of surfaces against each other.

The reason for this is the contact of two different substances of the dielectric itself. Atoms of one substance strip off electrons from another. After their separation, each of the bodies retains its discharge, but the potential difference increases

The use of static electricity in everyday life

Electricity can be your good helper. But for this you should know its features thoroughly and skillfully use them in the right direction. Used in technology various ways which are based on the following features. When small solid or liquid particles of substances come under the influence of an electric field, they attract ions and electrons. Charge is accumulating. Their movement continues already under the influence of an electric field. Depending on the equipment used, this field can be used to control the movement of these particles in various ways. It all depends on the process. This technology has become widely used in the national economy.

Painting

Paintable parts that move on the container, such as machine parts, are positively charged, while paint particles are negatively charged. This contributes to their quick pursuit of details. As a result of such a technological process, a very thin, uniform and fairly dense layer of paint is formed on the surface of the object.

Particles that have been dispersed by the electric field hit the surface of the product with great force. Due to this, a high saturation of the ink layer is achieved. At the same time, the consumption of the paint itself is significantly reduced. It remains only on the product itself.

Electrosmoking

Smoking is the impregnation of the product with the help of "wood smoke". Thanks to its particles, the product is very tasty. This helps to prevent its rapid deterioration. Electrosmoking is based on the following: particles of "smoke smoke" are charged with positive charges. As a negative electrode, as an option, the carcass of fish acts. These smoke particles fall on it, where they are partially absorbed. This process only takes a few minutes. And ordinary smoking is a very long process. So the benefit is clear.

Creating a pile

In order for a pile layer to form on any type of material in an electric field, it is grounded, and a layer of glue is applied to the surface. Then, through a special charged metal mesh, which is located above this plane, villi begin to pass. They very quickly orient themselves in a given electric field, which contributes to their uniform distribution. The villi fall onto the adhesive clearly perpendicular to the plane of the material. With the help of this unique technology, it is possible to obtain various coatings similar to suede or even velvet. This technique allows you to get various multi-colored drawings. To do this, use a pile of different colors and special patterns to help create a specific pattern. During the process itself, they are applied alternately to separate sections of the part itself. In this way it is very easy to get multi-colored carpets.

Dust collection

Not only the person himself needs clean air, but also very precise technological processes. Due to the presence a large number dust, all equipment becomes unusable ahead of its time. For example, the cooling system is clogged. Flying dust with gases is a very valuable material. This is due to the fact that the purification of various industrial gases is extremely necessary today. Now this problem is very easy to solve. electric field. How it works? Inside the metal pipe there is a special wire that plays the role of the first electrode. Its walls serve as the second electrode. Due to the electric field, the gas in it begins to ionize. Negatively charged ions begin to attach to the smoke particles that come with the gas itself. Thus, they are charged. The field contributes to their movement and settling on the pipe walls. After purification, the gas moves to the outlet. At large-scale thermal power plants, it is possible to capture 99 percent of the ash contained in the exhaust gases.

Mixing

Due to the negative or positive charge of small particles, their connection is obtained. The particles are distributed very evenly. For example, in the production of bread, it is not necessary to perform laborious mechanical processes to knead the dough. The grains of flour, which are pre-charged with a positive charge, enter with the help of air into a specially designed chamber. There, they interact with water drops, negatively charged and already containing yeast. They are attracted. The result is a homogeneous dough.

Conclusion

When studying physics at school, more attention should be paid to the practical application of physical knowledge in everyday life. At school, students should be introduced to the physical phenomena that underlie the operation of household appliances. Particular attention should be paid to the possible negative impact of household appliances on the human body. In physics lessons, students should be taught how to use instructions for electrical appliances. Before allowing a child to use a household electrical appliance, adults should make sure that the child has firmly mastered the safety rules for handling it. In order to avoid most unpleasant everyday situations, we need physical knowledge!

Physics is an exact and complex science. Therefore, the question arises, is there anyone in the 21st century to advance further in this science, study it more deeply and pay special attention?

I think that the bench is not yet empty, there are many universities with faculties studying this subject, and therefore people who are engaged in this science, of course, not everyone wants to connect their lives with physics, but when getting an education or already choosing a profession, physics can be a significant factor which will determine who you will be in the future. After all, physics is one of the most amazing sciences! Physics is developing so intensively that even the best teachers face great difficulties when they have to talk about modern science.