A person constantly encounters light phenomena. Everything that is connected with the appearance of light, its propagation and interaction with matter, is called light phenomena. Vivid examples of optical phenomena can be: a rainbow after rain, lightning during a thunderstorm, the twinkling of stars in the night sky, the play of light in a stream of water, the variability of the ocean and sky, and many others.

Schoolchildren receive a scientific explanation of physical phenomena and optical examples in the 7th grade when they begin to study physics. For many, optics will be the most fascinating and mysterious section in the school physics curriculum.

What does the person see?

Human eyes are designed in such a way that he can only perceive the colors of the rainbow. Today it is already known that the spectrum of the rainbow is not limited to red on one side and purple on the other. Red is followed by infrared, and violet is followed by ultraviolet. Many animals and insects are able to see these colors, but unfortunately humans cannot. But on the other hand, a person can create devices that receive and emit light waves of the appropriate length.

refraction of rays

Visible light is a rainbow of colors, and white light, such as sunlight, is a simple combination of these colors. If you place a prism in a beam of bright white light, then it will break up into colors or into waves of different lengths that it consists of. First comes red with the longest wavelength, then orange, yellow, green, blue, and finally violet, which has the shortest wavelength in visible light.

If you take another prism to catch the light of the rainbow and turn it upside down, it will combine all the colors into white. There are many examples of optical phenomena in physics, let's consider some of them.

Why the sky is blue?

Young parents are often perplexed by the most simple, at first glance, questions of their little why. Sometimes they are the hardest to answer. Almost all examples of optical phenomena in nature can be explained by modern science.

The sunlight that illuminates the sky during the day is white, which means that, theoretically, the sky should also be bright white. In order for it to look blue, some processes with light are necessary at the time of its passage through the Earth's atmosphere. Here's what happens: some of the light passes through the free space between the gas molecules in the atmosphere, reaching the earth's surface and remaining the same white color as at the beginning of the journey. But sunlight hits gas molecules, which, like oxygen, are absorbed and then scattered in all directions.

The atoms in the gas molecules are activated by the absorbed light and again emit photons of light in different wavelengths, from red to violet. Thus, some of the light goes to the earth, the rest goes back to the sun. The brightness of the emitted light depends on the color. Eight photons of blue light are released for every photon of red. Therefore, blue light is eight times brighter than red. Intense blue light is emitted from all directions from billions of gas molecules and reaches our eyes.

colorful arch

Once upon a time, people thought that rainbows were signs sent to them by the gods. Indeed, beautiful multi-colored ribbons always appear in the sky from nowhere, and then just as mysteriously disappear. Today we know that the rainbow is one of the examples of optical phenomena in physics, but we do not cease to admire it every time we see it in the sky. The interesting thing is that each observer sees a different rainbow, created by rays of light coming from behind him and from raindrops in front of him.

What are rainbows made of?

The recipe for these optical phenomena in nature is simple: water droplets in the air, light and an observer. But it is not enough for the sun to appear during the rain. It should be low, and the observer should stand so that the sun is behind him, and look at the place where it is raining or just rained.

A sunbeam coming from distant space overtakes a raindrop. Acting like a prism, the raindrop refracts every color hidden in the white light. Thus, when a white ray passes through a raindrop, it suddenly splits into beautiful multicolored rays. Inside the drop, they hit the inner wall of the drop, which acts like a mirror, and the rays are reflected in the same direction from which they entered the drop.

The end result is a rainbow of colors arching across the sky - light bent and reflected by millions of tiny raindrops. They can act like small prisms, splitting white light into a spectrum of colors. But rain is not always necessary to see a rainbow. Light can also be refracted by fog or fumes from the sea.

What color is the water?

The answer is obvious - water has a blue color. If you pour pure water into a glass, everyone will see its transparency. This is because there is too little water in the glass and its color is too pale to see it.

When filling a large glass container, you can see the natural blue tint of the water. Its color depends on how water molecules absorb or reflect light. White light is made up of a rainbow of colors, and water molecules absorb most of the red to green colors that pass through them. And the blue part is reflected back. So we see blue.

Sunrises and sunsets

These are also examples of optical phenomena that a person observes every day. When the sun rises and sets, it directs its rays at an angle to where the observer is. They have a longer path than when the sun is at its zenith.

The layers of air above the Earth's surface often contain a lot of dust or microscopic moisture particles. The sun's rays pass at an angle to the surface and are filtered. Red rays have the longest wavelength of radiation and therefore make their way to the ground more easily than blue rays, which have short waves that are beaten off by particles of dust and water. Therefore, during the morning and evening dawn, a person observes only a part of the sun's rays that reach the earth, namely red ones.

planet light show

A typical aurora is a multi-colored aurora in the night sky that can be observed every night at the North Pole. Shifting in bizarre shapes, huge streaks of blue-green light with orange and red spots sometimes reach more than 160 km in width and can stretch for 1600 km in length.

How to explain this optical phenomenon, which is such a breathtaking sight? Auroras appear on Earth, but they are caused by processes occurring on the distant Sun.

How is everything going?

The sun is a huge ball of gas, consisting mainly of hydrogen and helium atoms. They all have protons with a positive charge and electrons with a negative charge revolving around them. A halo of hot gas constantly spreads into space in the form of the solar wind. This countless number of protons and electrons are rushing at a speed of 1000 km per second.

When solar wind particles reach the Earth, they are attracted by the planet's strong magnetic field. The Earth is a giant magnet with magnetic lines that converge at the North and South Poles. The attracted particles flow along these invisible lines near the poles and collide with the nitrogen and oxygen atoms that make up the Earth's atmosphere.

Some of the earth's atoms lose their electrons, others are charged with new energy. After colliding with the protons and electrons of the Sun, they give off photons of light. For example, nitrogen that has lost electrons attracts violet and blue light, while charged nitrogen shines dark red. Charged oxygen gives off green and red light. Thus, the charged particles cause the air to shimmer with many colors. This is the aurora borealis.

Mirages

It should immediately be determined that mirages are not a figment of human imagination, they can even be photographed, they are almost mystical examples of optical physical phenomena.

There is a lot of evidence of the observation of mirages, but science can give a scientific explanation for this miracle. They can be as simple as a patch of water amid hot sands, or they can be stunningly complex, constructing visions of pillared castles or frigates. All these examples of optical phenomena are created by the play of light and air.

Light waves bend as they pass first through warm, then cold air. Hot air is more rarefied than cold air, so its molecules are more active and diverge over greater distances. As the temperature decreases, the movement of molecules also decreases.

Visions seen through the lenses of the earth's atmosphere can be highly altered, compressed, expanded, or inverted. This is because light rays bend as they pass through warm and then cold air, and vice versa. And those images that a light stream carries with it, for example, the sky, can be reflected on hot sand and seem like a piece of water, which always moves away when approached.

Most often, mirages can be observed at great distances: in deserts, seas and oceans, where hot and cold layers of air with different densities can simultaneously be located. It is the passage through different temperature layers that can twist the light wave and end up with a vision that is a reflection of something and presented by fantasy as a real phenomenon.

Halo

For most optical illusions that can be seen with the naked eye, the explanation is the refraction of the sun's rays in the atmosphere. One of the most unusual examples of optical phenomena is the solar halo. Basically, a halo is a rainbow around the sun. However, it differs from the usual rainbow both in appearance and in its properties.

This phenomenon has many varieties, each of which is beautiful in its own way. But for the occurrence of any kind of this optical illusion, certain conditions are necessary.

A halo occurs in the sky when several factors coincide. Most often it can be seen in frosty weather with high humidity. At the same time, there are a large number of ice crystals in the air. Breaking through them, the sunlight is refracted in such a way that it forms an arc around the Sun.

And although the last 3 examples of optical phenomena are easily explained by modern science, for an ordinary observer they often remain mystic and a mystery.

Having considered the main examples of optical phenomena, it is safe to assume that many of them are explained by modern science, despite their mysticism and mystery. But ahead of scientists there are still a lot of discoveries, clues to the mysterious phenomena that occur on planet Earth and beyond.

Electrical and optical phenomena in the atmosphere. atmospheric phenomena. Electrical and optical phenomena in the atmosphere are amazing and sometimes dangerous atmospheric phenomena.

Electrical phenomena in the atmosphere.

3. Electrical phenomena is a manifestation of atmospheric electricity (thunderstorm, lightning, aurora).

Thunderstorm - strong electrical discharges occurring in the atmosphere. Accompanied by gusty winds, heavy rain, flashes of bright light (lightning), and harsh sound effects (thunder). Thunder rumbles can be heard at a distance of up to twenty kilometers. The reason is cumulonimbus clouds. Electric discharges can occur between clouds, within the clouds themselves, between clouds and the earth's surface. A thunderstorm can be frontal during the movement of a cold or warm front of air masses or intramass. An intramass thunderstorm is formed when the air is heated locally. A thunderstorm is a very dangerous natural phenomenon for humans. In terms of the number of human lives claimed, a thunderstorm is in second place after floods. Curious scientists have determined that one and a half thousand thunderstorms occur simultaneously on Earth. Forty-six lightning strikes every second! Only at the poles and in the polar regions there is no thunderstorm.

Zarnitsa This is a light phenomenon in which clouds or the horizon are illuminated by lightning for a short time. Lightning itself is not observed. The reason is a far-reaching thunderstorm (at a distance of more than twenty kilometers). Thunder during lightning is not audible.

Polar Lights- multi-colored glow of the night sky at high latitudes. The reason is a significant fluctuation of the Earth's magnetic field. This releases a large amount of energy. The duration of this phenomenon can be from several minutes to several days.

Optical phenomena in the atmosphere.

4. Optical phenomena are the result of diffraction (refraction) of light from the Sun or the Moon (mirage, rainbow, halo).

Mirage is the appearance of an imaginary image of a really existing object. Usually imaginary objects appear upside down or heavily distorted. The reason is the curvature of the light rays due to the optical inhomogeneity of the air. Atmospheric heterogeneity appears when the air is heated unevenly at different heights.

Rainbow- a large multi-colored arc against the background of rain clouds. The outer part of the rainbow is red and the inner part is purple. Often, a secondary rainbow appears on the outside of the rainbow, in which the reverse alternation of colors. The reason for the occurrence is the refraction and reflection of light rays in droplets of water vapor. Rainbows can only be seen when the sun is low on the horizon.

Halo- light reddish arcs, circles, spots that appear around the Sun or Moon. The reason for the occurrence is the refraction and reflection of light rays from ice crystals in cirrostratus clouds.

5. Unclassified atmospheric phenomena are all phenomena that are difficult to attribute to any other type (squall, tornado, whirlwind, haze).

Squall it is an unexpected and sharp increase in wind within one or two minutes. The wind reaches speeds of more than 10 meters per second. The reason is the movement of ascending and descending air masses. The squall is accompanied by thunderstorms, heavy rain and cumulonimbus clouds.

Vortex is the rotational and translational movement of large masses of air. The diameter of the vortex can reach several thousand kilometers. Atmospheric whirlwinds: cyclone, typhoon.

Tornado or a tornado - a very strong vortex, which is a giant funnel or column of cloud. The diameter of such a column above the water can be up to 100 meters, and above the ground up to a kilometer. The height of the tornado reaches 10 kilometers.

Inside the funnel or column, when the air rotates, a zone of rarefied air is formed. The speed of air movement in the funnel has not yet been determined. There is simply no such daredevil who dared to fall into a funnel with devices. A tornado draws in water, sand, dust, and other objects and carries them over considerable distances. The life span of a tornado ranges from a few minutes to an hour and a half. It is formed in the heat and comes from a cumulonimbus cloud. People have not yet fully determined the mechanism of occurrence of tornadoes.

The atmosphere is a cloudy, optically inhomogeneous medium. Optical phenomena are the result of reflection, refraction and diffraction of light rays in the atmosphere.

Depending on the causes of occurrence, all optical phenomena are divided into four groups:

1) phenomena caused by the scattering of light in the atmosphere (twilight, dawn);

2) phenomena caused by the refraction of light rays in the atmosphere (refraction) - mirages, twinkling of stars, etc.;

3) phenomena caused by the refraction and reflection of light rays on drops and crystals of clouds (rainbow, halo);

4) phenomena caused by the diffraction of light in clouds and fog - crowns, gloria.

Dust caused by the scattering of sunlight in the atmosphere. Twilight is the transitional period from day to night (evening twilight) and from night to day (morning twilight). Evening twilight begins from the moment the sun sets and until complete darkness sets in, morning twilight - vice versa.

The duration of twilight is determined by the angle between the direction of the apparent daily motion of the Sun and the horizon; thus, the duration of twilight depends on geographic latitude: the closer to the equator, the shorter the twilight.

There are three periods of twilight:

1) civil twilight (the immersion of the Sun under the horizon does not exceed 6 o) - light;

2) navigational (immersion of the Sun under the horizon up to 12 o) - visibility conditions are greatly deteriorated;

3) astronomical (immersion of the Sun under the horizon up to 18 o) - it is already dark near the earth's surface, but dawn is still visible in the sky.

Dawn - a set of colorful light phenomena in the atmosphere, observed before sunrise or at sunset. The variety of colors of dawn depends on the position of the Sun relative to the horizon and on the state of the atmosphere.

The color of the firmament is determined by the scattered visible rays of the sun. In a clean and dry atmosphere, light scattering occurs according to Rayleigh's law. Blue rays scatter about 16 times more than red rays, so the color of the sky (scattered sunlight) is blue (blue), and the color of the Sun and its rays near the horizon is red, because. In this case, light travels a longer path in the atmosphere.

Large particles in the atmosphere (drops, dust particles, etc.) scatter light neutrally, so clouds and fog are white. With high humidity, dustiness, the entire sky becomes not blue, but whitish. Therefore, by the degree of blueness of the sky, one can judge the purity of the air and the nature of the air masses.

atmospheric refraction - atmospheric phenomena associated with the refraction of light rays. Refraction is due to: twinkling of stars, flattening of the visible disk of the Sun and Moon near the horizon, an increase in the length of the day by several minutes, as well as mirages. A mirage is a visible imaginary image on the horizon, above the horizon or below the horizon, due to a sharp violation of the density of air layers. There are inferior, superior, lateral mirages. Moving mirages - "Fata Morgana" are rarely observed.

Rainbow - this is a light arc, painted in all colors of the spectrum, against the background of a cloud illuminated by the Sun, from which raindrops fall. The outer edge of the arc is red, the inner edge is purple. If the Sun is low on the horizon, then we see only half of the circle. When the Sun is high, the arc becomes smaller, because. the center of the circle falls below the horizon. At a height of the Sun greater than 42 about the rainbow is not visible. From an airplane, you can observe a rainbow of almost a full circle.

A rainbow is formed by the refraction and reflection of sunlight in water droplets. The brightness and width of the rainbow depends on the size of the droplets. Large drops give a smaller but brighter rainbow. With small drops, it is almost white.

Halo - these are circles or arcs around the Sun and the Moon, arising in the ice clouds of the upper tier (most often in cirrostratus).

crowns - light, slightly colored rings around the Sun and Moon, arising in the water and ice clouds of the upper and middle tiers, due to the diffraction of light.

At school, the 6th grade studies the topic "Optical phenomena in the atmosphere". However, it is of interest not only to the inquisitive mind of a child. in the atmosphere, on the one hand, they combine a rainbow, a change in the color of the sky during sunrises and sunsets, which has been seen by everyone more than once. On the other hand, they include mysterious mirages, false Moons and Suns, impressive halos that in the past terrified people. The mechanism of formation of some of them remains unclear even today, however, the general principle by which optical phenomena "live" in nature has been well studied by modern physics.

air shell

The Earth's atmosphere is a shell consisting of a mixture of gases and extending for about 100 km above sea level. The density of the air layer changes with distance from the earth: its highest value is at the surface of the planet, with height it decreases. The atmosphere cannot be called a static formation. The layers of the gaseous envelope are constantly moving and mixing. Their characteristics change: temperature, density, speed of movement, transparency. All these nuances affect the sun's rays rushing to the surface of the planet.

Optical system

The processes occurring in the atmosphere, as well as its composition, contribute to the absorption, refraction and reflection of light rays. Some of them reach the target - the earth's surface, the other is scattered or redirected back into outer space. As a result of the curvature and decay of part of the rays into a spectrum, and so on, various optical phenomena are formed in the atmosphere.

atmospheric optics

At a time when science was just in its infancy, people explained optical phenomena based on the prevailing ideas about the structure of the universe. The rainbow connected the human world with the divine, the appearance of two false Suns in the sky testified to the approaching catastrophes. Today, most of the phenomena that frightened our distant ancestors have received a scientific explanation. Atmospheric optics is engaged in the study of such phenomena. This science describes optical phenomena in the atmosphere based on the laws of physics. She is able to explain, during the day, and during sunset and dawn, it changes color, how a rainbow is formed and where mirages come from. Numerous studies and experiments today make it possible to understand such optical phenomena in nature as the appearance of luminous crosses, Fata Morgana, iridescent halos.

Blue sky

The color of the sky is so familiar that we rarely wonder why it is so. Nevertheless, physicists know the answer well. Newton proved that, under certain conditions, it decomposes into a spectrum. When passing through the atmosphere, the part corresponding to the blue color is scattered better. The red section is characterized by a longer wavelength and is inferior to the violet in terms of the degree of scattering by 16 times.

At the same time, we see the sky not purple, but blue. The reason for this lies in the peculiarities of the structure of the retina and the ratio of parts of the spectrum in sunlight. Our eyes are more sensitive to blue, and the violet part of the star's spectrum is less intense than blue.

scarlet sunset

When people figured it out, optical phenomena ceased to be evidence or an omen of terrible events for them. However, the scientific approach does not interfere with receiving from colorful sunsets and gentle dawns. Bright reds and oranges, along with pinks and blues, gradually give way to night darkness or morning light. It is impossible to observe two identical sunrises or sunsets. And the reason for this lies in the same mobility of the atmospheric layers and changing weather conditions.

During sunsets and sunrises, the sun's rays travel a longer path to the surface than during the day. As a result, diffused violet, blue and green go to the sides, and direct light turns red and orange. Clouds, dust or ice particles suspended in the air contribute to the picture of sunset and dawn. The light is refracted as it passes through them, and colors the sky in a variety of shades. On the part of the horizon opposite from the Sun, one can often observe the so-called Belt of Venus - a pink band separating the dark night sky and the blue day sky. The beautiful optical phenomenon, named after the Roman goddess of love, is visible before dawn and after sunset.

rainbow bridge

Perhaps no other light phenomena in the atmosphere evoke so many mythological plots and fairy-tale images as those associated with the rainbow. The arc or circle, consisting of seven colors, is known to everyone since childhood. A beautiful atmospheric phenomenon that occurs during rain, when the sun's rays pass through the drops, fascinates even those who have thoroughly studied its nature.

And the physics of the rainbow today is no secret to anyone. Sunlight, refracted by drops of rain or fog, splits. As a result, the observer sees seven colors of the spectrum, from red to violet. It is impossible to define the boundaries between them. Colors blend smoothly into each other through several shades.

When observing a rainbow, the sun is always located behind the person's back. The center of Irida's smile (as the ancient Greeks called the rainbow) is located on a line passing through the observer and the daylight. A rainbow usually appears as a semicircle. Its size and shape depend on the position of the Sun and the point at which the observer is located. The higher the luminary above the horizon, the lower the circle of the possible appearance of a rainbow falls. When the Sun passes 42º above the horizon, an observer on the Earth's surface cannot see the rainbow. The higher above sea level a person who wants to admire the smile of Irida is located, the more likely that he will see not an arc, but a circle.

Double, narrow and wide rainbow

Often, along with the main one, you can see the so-called secondary rainbow. If the first is formed as a result of a single reflection of light, then the second is the result of a double reflection. In addition, the main rainbow is distinguished by a certain order of colors: red is located on the outside, and purple is on the inside, which is closer to the surface of the Earth. The side "bridge" is the spectrum reversed in sequence: violet is at the top. This happens because the rays come out at different angles during double reflection from a raindrop.

Rainbows vary in color intensity and width. The brightest and rather narrow ones appear after a summer thunderstorm. Large drops, characteristic of such rain, give rise to a highly visible rainbow with distinct colors. Small drops give a more blurry and less noticeable rainbow.

Optical phenomena in the atmosphere: aurora

One of the most beautiful atmospheric optical phenomena is the aurora. It is characteristic of all planets with a magnetosphere. On Earth, auroras are observed at high latitudes in both hemispheres, in zones surrounding the planet's magnetic poles. Most often you can see a greenish or blue-green glow, sometimes supplemented by flashes of red and pink along the edges. The intense aurora borealis is shaped like ribbons or folds of fabric, turning into spots as it fades. Stripes several hundred kilometers high stand out well along the lower edge against the dark sky. The upper limit of the aurora is lost in the sky.

These beautiful optical phenomena in the atmosphere still keep their secrets from people: the mechanism of the occurrence of certain types of luminescence, the cause of the crackling that occurs during sharp flashes, has not been fully studied. However, the general picture of the formation of auroras is known today. The skies above the north and south poles are adorned with a greenish-pink glow as charged particles from the solar wind collide with atoms in Earth's upper atmosphere. The latter, as a result of the interaction, receive additional energy and emit it in the form of light.

Halo

The sun and moon often appear before us surrounded by a glow resembling a halo. This halo is a highly visible ring around the light source. In the atmosphere, most often it is formed due to the smallest particles of ice that make up high above the Earth. Depending on the shape and size of the crystals, the characteristics of the phenomenon change. Often the halo takes the form of a rainbow circle as a result of the decomposition of the light beam into a spectrum.

An interesting variation of the phenomenon is called parhelion. As a result of the refraction of light in ice crystals at the level of the Sun, two bright spots are formed, resembling a daylight star. In historical chronicles one can find descriptions of this phenomenon. In the past, it was often considered a harbinger of formidable events.

Mirage

Mirages are also optical phenomena in the atmosphere. They arise as a result of the refraction of light at the boundary between layers of air that differ significantly in density. The literature describes many cases when a traveler in the desert saw oases or even cities and castles that could not be nearby. Most often these are "lower" mirages. They arise over a flat surface (desert, asphalt) and represent a reflected image of the sky, which seems to the observer to be a reservoir.

The so-called superior mirages are less common. They form over cold surfaces. Superior mirages are straight and inverted, sometimes they combine both positions. The most famous representative of these optical phenomena is Fata Morgana. This is a complex mirage that combines several types of reflections at once. Real-life objects appear before the observer, repeatedly reflected and mixed.

atmospheric electricity

Electrical and optical phenomena in the atmosphere are often mentioned together, although their causes are different. The polarization of clouds and the formation of lightning are associated with processes occurring in the troposphere and ionosphere. Giant spark discharges are usually formed during a thunderstorm. Lightning occurs inside clouds and can strike the ground. They are a threat to human life, and this is one of the reasons for the scientific interest in such phenomena. Some properties of lightning are still a mystery to researchers. Today, the cause of ball lightning is unknown. As with some aspects of aurora and mirage theory, electrical phenomena continue to intrigue scientists.

Optical phenomena in the atmosphere, briefly described in the article, are becoming more and more understandable for physicists every day. At the same time, they, like lightning, never cease to amaze people with their beauty, mystery and sometimes grandiosity.

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The purpose of the lesson: to form an idea of ​​\u200b\u200boptical phenomena in the atmosphere.

Expected result: students should know / understand and explain how atmospheric phenomena occur due to the reflection of sunlight; electrical phenomena.

Basic terms and concepts: optical phenomena in the atmosphere, rainbow, mirage, halo, aurora, lightning, “St. Elmo's Lights”.

Resources:
– textbook – pp. 106–109;
– electronic supplement to the textbook;
– presentation for the lesson.

Equipment:
- Projector;
- Screen;
- The teacher's computer;
– Laptops on each desk;
– Vessel in oriental style;
- Suit for Old Man Hottabych.

During the classes

- Are there children, a blanket,
To cover the whole Earth?
To have enough for everyone
Was it not visible?
Don't fold, don't unfold
Do not feel, do not look?
Let rain and light through
Is there, but is it not?
- What is this blanket? (Atmosphere is the air envelope of the Earth.)

And we continue to study the topic “Atmosphere” with you. First, I'll ask you a few questions:

1. What does the Earth's atmosphere consist of? (A mixture of gases, tiny drops of water and ice crystals, dust, soot, organic matter.)

2. In what form is moisture contained in the air? (Water vapor, water droplets and ice crystals.)

3. The atmosphere is not homogeneous, does it have several layers? (Tropo-strato-meso-thermo-exo-ionosphere.)

4. In what layers does the aurora appear? (Ionosphere.)

- Polar lights, lightning, mirages frightened people in ancient times. Today, scientists have managed to uncover the secrets of these mysterious phenomena. And the topic of our lesson is “Optical phenomena in the atmosphere”.

And what is this mysterious vessel on my table? You do not know? Let's get a look?

(He opens the vessel, smoke pours out of it, old Hottabych appears.)

– Apchi! Greetings, my wise lord! (Dalley words Hottabycha, played by one of the students are underlined.)
- Where are you from? Are you from the theatre?
– Oh no, my lord! I'm from this vessel!
– So you..?
– Yes, I am the mighty and glorified genie in all four countries of the world Hassan Abdurakhman ibn Hottab, that is, the son of Hottab!
- Hottabych?!
– And who are these beautiful youths?
- BUT these are students of the 6th "A" class, and now we have a geography lesson.
– Geography lesson! Know, O most beautiful of the beautiful, that you are unheard of lucky, for I am rich in knowledge of geography. I will teach you, and you will become famous among the students of your school and among the students of all schools in your region!
– We are very happy about this, dear Hottabych.
– And what are these magical black boxes that lie in front of you?
– These are computers with which today's children learn geography. I invite you, dear Hottabych, to work with us today. And I will ask the guys to open the screen of the lesson "Optical phenomena in the Atmosphere. What do you think, what are optical phenomena? (light, visual).
Today we will get acquainted with some optical phenomena, fill in the table that lies in front of you. Well, our esteemed Hottabych will tell us how the ancient scientists represented this or that phenomenon.

So let's get started!

Phenomena associated with the reflection of sunlight.

Rainbow - The summer rain had passed, and the sun shone again. And as if by magic, a rainbow-arc appeared in the sky.

I know that the god of ancient Babylon created the rainbow as a sign that he decided to stop the Flood.

What do modern scientists think about this?

Sunlight appears white to us, but it is actually made up of 7 colors of light: red, orange, green, blue, indigo and violet. Passing through the drops of water, the sun's ray is refracted and breaks up into different colors. That's why after the rain or near the waterfalls you can see the rainbow. (make an entry in the table).

– Many desert travelers witness another atmospheric phenomenon -Mirage.

The ancient Egyptians believed that a mirage is the ghost of a country that no longer exists.

(Children study this section in the electronic application and say the modern version)

Why do mirages occur? This happens when hot air above the surface rises. Its density begins to increase. Air at different temperatures has different densities, and a beam of light, passing from layer to layer, will bend, visually bringing the object closer. M. arise over a hot (desert, asphalt), or, on the contrary, over a chilled surface (water).

Halo . In frosty weather, pronounced rings appear around the Sun and Moon -Halo.

“It means that at this time there is a sabbath of witches.

(Children study this section in the electronic application and say the modern version.)

They occur when light is reflected in the ice crystals of cirrostratus clouds. Crowns - several rings nested in each other. (Records.)
Air does not conduct electricity, but in some cases it is found that it is simply overflowing with electricity.

Phenomena associated with electricity.

Polar Lights - Residents of the polar regions can admire the Northern Lights.

- E then self-luminous air exits through a hole in the Earth.

(Children study this section in the electronic application and say the modern version.)

The sun sends a stream of electrically charged particles to the Earth, which collide with air particles and begin to glow. (Records.)

Lightning - "A fire arrow is flying, no one will catch it - neither the king, nor the queen, nor the fair maiden.

- It is God Perun who strikes a snake with his stone weapon.

(Children study this section in the electronic application and say the modern version.)

A visible electrical discharge between clouds, or between a cloud and the ground. Lightning Thunder. Air can heat up inside lightning up to 30.000 gr. (This is 5 times more than on the surface of the Sun.)

Types of lightning (linear and ball), why are they dangerous? (Records.)

Another phenomenon associated with the electric glow of the atmosphere

"Fire of Saint Elmo".

Sailors consider it a bad omen.

(Children study this section in the electronic application and say the modern version.)

Today we got acquainted with some unusual phenomena in nature.

– Thanks to Hottabych, we learned about the views of the ancients on optical phenomena in the atmosphere.

– Well, I found out how your modern scientists explain many mysterious phenomena.

(If there is time: I suggest you test yourself with a quiz.)

Today you did a good job, this topic is very complex, and you will study it more deeply in the course of physics in grades 10-11.

D.Z. : Take the quiz for this lesson.

For those who wish: find out from additional sources of information what unusual atm. phenomena have ever taken place in your area. How are they described?