Why is snow white, although a separate snowflake transparent? Why snow white? What is lighter: pure snow in moon night black velvet on a sunny day
I am a snowball in the hands of a cherish and my breathing warm.
Look, my snowball turned into a rod!
Ah, do not stand on the way! He hurries the spring to find!
Galina Mikhailovna Novitskaya
Galina Mikhailovna Novitskaya (1933-2000) - Soviet poetess, prose, translator.
Most of Galina New Creativity - these are poems for children,
in which poetess created a unique atmosphere of beauty and fragility of the world.
Interest Chest: Snow
Physics around us
This year, the winter in Kursk was delayed - no way wants to let the brazdes of the board and remove the snow from the courtyard :-) It pleases the sun with warmth, but it cannot cope with snowdrifts ... From the work of the shovel and transferring snow from the yard to the garden - the snow amount does not change: - ) Someone chases the root snow, arranging dancing with tambourine, someone breed fires and sings sonorous songs - running winter and attracting spring ...
But neither one or the other is not our method ;-)
Let's try to be welcome, yes, the snow is unconventional, but, hopefully, the effective way :-)))))))
Your attention riddles and proverbs about snow, inimitable winter poetry performed by Ivan Alekseevich Bunin and Robert Ivanovich christmas, masterpieces of world painting and my adorable physics!
Riddles about the snow
- In winter heats, in the spring smolders, in the summer dies, it comes to life in the fall.
- I lay, lying, and ran to the river.
- On the courtyard mountain, and in the waterproof water.
Proverbs about snow
- Snow is the root of cormalice - a warm casing.
- More snow in the fields - more bread in the covers.
- Snow inflated - bread will arrive; Water will fall out - the hay will go.
Goryushkin-Sorokopudov Ivan Polech (05.11.1873-29.12.1954) - Russian and Soviet painter, schedule and teacher. Honored Art Worker of the RSFSR.
In short - winter solstice. The night is short and the strider is much cooled :-) Inrogenous ... Celtic Halloween ;-) And also ... Pamper yourself with delicious winter landscapes on the green page "Seasons: Winter".
Snow winter warms, spring smashes, in the summer dies, in the fall comes to life
Snow Earth-Kormilice - Warm Casing
Casing It is the outerwear from the skin - the sheepskin Tulup. Sheepskin coat it's a long, not covered with cloth fur coat. It turns out that winter-mother clothes the land in snow fur coat. And now attention - interest Ask ;-)
Was us a fur coat and warms the earth?
What would you say if you had to confine that noise was not heating at all? You would think of course you joke with you. And if you began to prove this statement on a number of experiments? Do, for example, such experience. Notice how much the thermometer shows, and eat it in a fur coat. After a few hours, remove. You will make sure that he did not even get sick on a quarter of a degree: how much did it show before, so many shows now. That's the proof that the fur coat does not warm. You might suspect that fur coats are even cold. Take two ice bubbles; One snatch into a fur coat, leave the room unclipped in the room. When the ice in the second bubble melts, expand the fur coat: you will see that he almost started to melt. So, the fur coat not only did not warmer ice, but as if even refrigerated him, slowing down the melting!
What can I argue? How to disprove these arguments? In no way. Fur coats do not really warm if under the word "warm" meaning of heat. The lamp warms, the stove warms, the human body warms, because all these items are heat sources. But the fur coat in this sense does not warm the word in this sense. She does not give his heat, but only prevents the warmth of our body to leave him. That is why the warm-blooded animal, the body of which itself is a source of heat, will feel in the fur coat warmer than without it. But the thermometer does not generate their own heat, and its temperature will not change from the fact that we snatch it in a fur coat. The ice, wrapped in a fur coat, retains her longer low temperaturebecause the fur coat is a very bad warmth conductor - slows down access to it from the outside, from room air.
In the same sense, like a fur coat, the snow warms the earth; Being, like all powdered bodies, a bad conductor of heat, it prevents the heat from the soil covered with them. In the soil, a protected layer of snow, the thermometer shows often ten more degrees than in soil, not covered with snow.
So, to the question, whether the fur coat warms us, it is necessary to answer that the fur coat only helps us to heal themselves. Rather, it would say that we warm the fur coat, and not she.
("Was the fur coat? Entertaining Physics ", Jacob Isidovich Perelman)
Oscar Claude Monet (Oscar-Claude Monet; 14.11.1840-05.12.1926) - French painter-landscape system, one of the founders of impressionism.
Polenova Elena Dmitrievna (11/27/1850-19.11.1898) - Russian artist, schedule, painter, master of decorative design, one of the first artists-illustrators of the children's book in Russia, one of the founders of Modern style in Russian art. Sister of painter Vasily Dmitrievich Polenova.
And for complete picture more interest Ask ;-)
What protects from the cold is better:
Wooden wall or layer of snow of the same thickness?
Snow protects against heat loss better than a tree: the thermal conductivity of snow is 2.5 times less. A slight thermal conductivity of snow caused its "heating" soil action; Covering the Earth, he slows the loss of heat. Bad thermal conductivity of snow is due to its loose addition. The snow concludes up to 90% of air - not only between snowflakes, but also inside them: in the ice crystals of snow there are air bubbles.
("What protects from the cold is better: a wooden wall or a layer of snow of the same thickness? Do you know physics?", Jacob Isidovich Perelman)
Volkov Efim Efimovich (04/04/1844-17.02.1920) - Russian painter, landscape system, a member of the partnership of mobile art exhibitions, a valid member and academician of the Imperial Academy of Arts.
Inimitable winter poetry
"Epishetic Night", 1886-1901 Ivan Alekseevich Bunin
|
Dark Yelnik Snow, like fur, Motionally froze their branches, Highly he rose over the forest, Forest thickets fleece, - Ubaul a blizzard gray Sleep mysteriously slender thickets, |
Silence, - Even the branch is not loussed! Silence, - and perhaps it is close ... In distant couples, where branches and shadows Fire Breakwood Fire Diamond radiant and bright And above the forest is higher and higher |
Wielz Ivan (Johann-Alexander) Augustusich (1866-1926) - Russian painter-landscape of Austrian origin.
The moonlight fills the baptized night with fairy charm and brings a delightful paint palette, the transforming winter landscape and our mood with you ;-) Snow over the moonlight fascinates, blistering with diamonds, and excites our imagination with bizarre images ... and now attention - interest Ask ;-)
What is lighter: pure snow in the lunar night
Or black velvet on a sunny day?
Nothing seemingly surpasses black velvet in black and white snow in white. However, these long-standing classic samples of black and white, dark and light are completely different when they are suitable with an impartial physical instrument - a photometer. Then it turns out that, for example, the chinful velvet under the rays of the sun is lighter than the cleanest snow in the moon night. The reason that the black surface, whatever the dark it seems, does not absorb completely all the rays of visible light falling on it. Even soot and platinum mobile - the most black paints, which we know, dispel about 1-2% of the light falling on them. Let us dwell on the figure of 1% and we assume that the snow dissipates all 100% of the light falling on it (which is unconditionally exaggerated). It is known that the lighting given by the Sun, 400,000 times stronger than the lighting of the moon. Therefore, 1% of sunlight scattered by black velvet, thousands of times more intense than 100% of the lunar light dissipated by snow. In other words, black velvet with sunlight is many times the lighter snow, illuminated by the moon.
The said belongs, of course, not only to the snow, but also to the best Belim (the most bright of them - lithopon - scatter 91% of the light falling on them). Since no surface, if it is not late, can not discard more light than it falls, and the moon sends 400,000 times less than the sun, rather than the sun, then the existence of such white paint, which in the lunar light would be objectively brighter Black paint on a sunny day.
("What is lighter: black velvet on a sunny day or pure snow on a lunar night? Do you know physics?", Jacob Isidovich Perelman)
§ The charming magic of the lunar light in an integrated collection of quality problems in physics on the green page "Physics and fiction: Optics (Moonlight)" - can the book read the book at the light of the full moon?
§ I suggest readers to go to a fascinating walk through the lunar poetry and painting and pamper themselves with the interests of the variability and impermanence of the color and size of the moon on the green page "The description of the moon in poetic works".
Ludwig Munte (Ludvig Munthe; 03/11/1841-30.03.1896) - Norwegian painter.
Inimitable winter poetry
"These snowflakes blend ...", Robert Ivanovich christmas
The mixture of these snowflakes. This snow is ash.
As a belated revenge of the summer richness of herbs.
These snowflakes are a ghostly wing.
White nonsense multiple number ...
Of this snow. This snow pain:
In the sky herself concerned, become on Earth.
This snow period. This snow circle.
Strange streets of roads, not suddenly understood.
Learned by heart, started with Azov,
This snow sadness. This snow is call.
Slow Mark Falling from Darkness
In the thirsty palm of winter touches.
Meshchersky Arseny Ivanovich (1834-1902) - Russian painter-landscape system; Landscapes from the nature of South and Northern Russia, Crimea and the Caucasus.
Interesting about the ice and the birth of snowflakes
Ice - Complex hex crystals formed by water, frozen at a temperature of 0 ° C or lower. Loda has less density than water, so does not sink. When the water vapors are condensed at temperatures below the freezing point, ice crystals are formed. This is mainly in high cigarette clouds, as well as in the part of other clouds that looks sulfur. The accumulation of such crystals generates snowflakes. The process can occur at the surface of the Earth, which leads to the formation of the ENEY. And now attention - interest Ask ;-)
Why is ice transparent, and snow white?
Snow has a white color for the same reason as it seems white tooling glass, sugar and in general all sorts of crushed transparent substances. Melt the ice in a mortar or dawn it with a knife - and you will have a white powder. This color is due to the fact that the rays of the light, penetrating into small pieces of transparent ice, do not pass through them, and are reflected inside at the boundaries of ice and air (full internal reflection). The surface is randomly dispersing in all directions falling on her rays, perceived by the eye as white.
So, the cause of white snow is its fragmentation. If the gap between the snowflakes fill with water, the snow loses the white color and becomes transparent. Such an experience is not difficult to do: if you are embanking snow in the jar and naply water there, the snow on your eyes from white is made colorless, transparent.
("Why is ice transparent, and snow white? Do you know physics? ", Jacob Isidovich Perelman)
Albert Birstadt (Albert Bierstadt; 1830-1902) - American artist landscape officer, representative of the Dusseldorf art school.
Georg Eduard Otto Saala (Georg Eduard Otto Saal; 03/11/1817-03.10.1870) - German painter.
The materials of this article will use it not only to apply lessons physics and fiction
but in extracurricular work
. I hope that the decision offered in the article qualitative Tasks in Physics not only helps to encourage interest in schoolchildren to the subject, but also to expand their knowledge and cultural horizons ;-)
And let's hope that winter-mother will appreciate this article on dignity and give way to spring ;-)
For considerable loyalty, I suggest readers of green pages urgently top up the chest of interest to the qualitative tasks of the physics dedicated to the snow.
Waiting for your suggestions in the comments.
Quality challenges on physics dedicated to snow
Task number 1
Why is the fierce frost, the stronger the snow creaks under his feet?
Answer: Skyrplay of snow with significant frosts is explained by the fact that the snowflakes under the pressure of the man's legs, the crawls of the sleigh or wheels of the car are not melted, as with more high temperatures, but fluttered and moved. And the lower the temperature, the stronger the snow creaks.
Task number 2.
"More snow in the fields - more bread in the covers" rightly approves the ancient Russian proverb. Snow cover is a kind of giant fur coat, protecting the surface of the earth from frost and cold winds. And what other important role is the snow cover?
Answer: Snow cover is a source and keeper of moisture, so necessary fields: "Snow inflated - bread will arrive; Water will fall out - the hay will go. " Spring snow gives molten water saturated with oxygen. No wonder Snowy amelioration is considered as one of the most important conditions for obtaining high and sustainable yields.
Task number 3.
Early spring, as well as after short-term winter thaws, at the foot of the trees are formed by holes in the snow. Explain the reasons for their occurrence.
Answer: At first glance, the reason for the occurrence of holes in the snow is very simple. During the life of the spring or winter Dip The sun rays warm the trunk of the tree well, which contributes to the dark color of its surface and the fact that the rays are low standing sun Extremely perpendicular to the surface of the trunk. The thermal conductivity of the tree is very low, so it relatively slowly gives warmth. Plots adjacent to the trunk under the action of this heat are gradually pushed, and the resulting a snowy hole is formed. From the south side, where the trunk of a tree receives more sunlight (in the northern hemisphere), the depth of the wells is usually greater - after all, the south side of the tree warms up stronger.
All this is so. Nevertheless, the explanation cannot be considered exhaustive. It does not explain why at the foot of the wooden pillars snow wells, as a rule, is less or no in general. The fact is that in the spring and during the winter thaws, the tree seems to be waking up - the internal juices begin to the branches from its roots. Together with them, the trunk of the tree and the branches get warmth from underground layers pearated roots. Thus, the tree trunk is heated not only from the outside (due to the absorption of the energy of the solar rays), but also from the inside (due to the rise of juices for capillaries inside the tree trunk).
()
|
Ivanovsky Ivan Konstantinovich (Hovhannes Avazyan; 07/29/1817-02.05.1900) - the world-famous Russian marinist artist, battalist, collector, patron.
§ In the picture of Ivan Konstantinovich Aivazovsky depicted a well caravel.
I suggest readers to look at the green page "Casket of quality problems in physics: elements of static: equilibrium bodies, moment of force, simple mechanisms."
The main chip of this collection is a problem about three wells, and also ;-) Cognitive interest about the inclined Nevyanskaya Tower - the architectural pearl of the Urals, shrouded legends under the most flag-weather with the coat of arms of Demidov ...
Task number 4.
Why in mountainous areas drops significantly more snow than on the plains?
Answer: In the mountains, the distance from the clouds to the Earth is significantly less than on flat terrain. The smaller this distance, the smaller, with other things being equal, the likelihood that the falling snow melts or evaporates. That is why in mountainous areas there is much more snow than on the plains.
Task number 5.
Why snow delayed on the branches of trees?
Answer: Try to twist sand on a tree branch, devoid of leaves. He practically can not be delayed on it and will almost completely wake up to the ground. Unlike sand, the snow can accumulate on the naked branches, forming, sometimes, such heavy caps that branches are rolled.
Snow outgrowths on trees are formed under the snowfall in quiet weather, when the air temperature is close to 0 ° C. Under these conditions, a variety of processes inside the snow are quite intensively: tapping and freezing, evaporation and crystallization. They lead to the formation of connections between the fallen snowflakes and the surface of the branches, as well as between the snowflakes themselves. The first snowflakes are tapping and approximate to the branches, forming thin floods on them. Subsequent snowflakes are already subject to this land. So gradually on the branches grow large snow caps, capable of keeping even with wind gusts (if, of course, these impulses are not too strong).
("Snow and ice. Physics in Nature, "Lev Vasilyevich Tarasov)
Peter Mörk Mönsted (Peder Mork Monsted; 10.12.1859-20.06.1941) - Danish painter, recognized master landscape, representative of the Golden Age of Danish painting.
Task number 6.
Why dark snow with time?
Answer: Snow darkens primarily because dust and soot are deposited on it available in the air. But the point is not only in this, the snow darkening means that it has become less reflected by the sun's rays and, it means to absorb them more. Thaw and movement of water vapors from the depths of the snow cover to its surface - all this leads to the filling of the air pores of the surface layer of melt water and ice, leads to the seal of this layer and to the formation of NAST. As a result, the full internal reflection decreases, the penetration of sun rays into the depths of snow cover increases, the absorption of light inside the cover increases - the snow is even more dark.
Note that in the spring the moisturizing snow and contamination of its surface reduce the proportion of light, reflected by the snow cover, up to 30%. In other words, for the period from the snow falling to the spring melting, the reflectivity of the snow cover decreases more than 3 times.
("Snow and ice. Physics in Nature, "Lev Vasilyevich Tarasov)
Task number 7.
What is longer freed from snow: hillocks or lowers?
Answer: The lowers are exempted longer from snow, as the cold air is heavier warm and lowered from the hillocks down - in low-spirits. The hillock takes place not only more warm air, but also more sunlight, especially southern slopes of hillocks.
For curious:
Red hill - One of the most ancient Slavic holidays, symbolizing the final and irrevocable arrival of spring!
With the spread of Christianity was timed to the first Sunday after Easter (the so-called Fomin Day). In 2018, the Red Gorka will be celebrated on Sunday - April 15.
In the old days in each village there was a hill, a horushka, a hillow, where the village rustic walking was held. Such sublime places were faster than others were released from snow., they started green and it was here that the first spring round dances were launched ... Such slides were called in the people Red, that is, beautiful!
Red hill In Russia, there was sometimes weddings. Went in the people, on this wrong, the proverb: "Who on a red hill marries - the forever can not be broken!" Our ancestors believed that the marriage union was concluded on this day would be filled with love and well-being.
Invested in this proverb and a very pragmatic message - wedding felling was terribly desirable ;-) spend in spring, to sowing, so that they are not distracted by field work.
Korzukhin Alexey Ivanovich (03/23/1835-30.10.1894) - Russian genital painter, academician of the Imperial Academy of Arts, one of the founders of the partnership of mobile art exhibitions.
§ I suggest readers of green pages to make a small journey to the world of Slavic mythology: Comoedian - A two-week celebration of the Spring Equinox Day - the beginning of the astronomical spring. And also ... Poems about the spring, delightful spring landscapes and luxurious floral still lifes on the green page "Seasons: Spring".
I wish you success in an independent decision
qualitative tasks in physics!
When a Russian person is asked to imagine winter, he sees the first thing in his imagination snow, snow-white cover, which watched everything around. We are so accustomed to the color of snow that we do not even think why snow white.
Why snow white
All colors perceived by us depend on the sun's rays. Black items completely absorb sunlight, Therefore, they are perceived by black. And if the subject completely reflects the ray of the sun, then the color will seem white.
What is snow, in fact? This is frozen water, hex ice floes. And water and ice colorful. Why then snow white? Ice remains colorless, because it passes through itself sunbeam. Yes, and each snowflake would have missed all the world and also did not have colors. But snowflakes usually fall on each other in a messy movement. And together they become opaque, but white.
To figure out why snow is white, why he reflects the rays of the sun, we need to look at the composition of the snow. The snow is formed from snowflakes, and snowflakes from a huge amount of crystals. These crystals are not smooth, but with edges. This is the answer to our question, why the snow is white. It is from the edges that the sunlight is reflected.
Water in the atmosphere is a pair, it freezes, and transparent crystals are formed. From the movement of the air, the crystals are freely moving up, then down. In this chaotic motion, the crystals are connected to each other. And when too many crystals are going together, then they begin to fall on Earth already in the form of snowflakes usually.
It turns out, the color of snow is white, because the light of the sun, which it reflects is white. Think if the sun beam became green or yellow, then the color of the snow was the same. Surely, many noticed that during sunrise or sunset, it seems to us that the rays of the sun become pinkish, so the snow at that moment see us pink.
Is there snowing other color
Who can give an affirmative answer to this incomplete question?! Do not learn this idea right away. In fact, it happened that such that fell out colored snow. For example, once Charles Darwin described one such case. The case was during one expedition. Looking at the hooves of Moulov, Ch. Darwin saw that they were covered with red spots. It happened when Mula walked on the snow felling. It turned out that the red snow was formed from the presence of red pollen in the air at a time when snow began to fall.
The question of why snow is white, I will sign every person since childhood. But not all children, and adults, know the correct answer, for what reason small snowflakes are not blue or green. Everyone knows that snow is frozen water, more precisely ice. But since the ice is transparent and is able to skip the light through itself, then why snow drifts that are covered far away are frozen, and have a very distinct color?
In the past century, when there were no such developed technologies, allowing to study all natural processes, scientists beat over the question of why snow white. However, the answer never found. Only when the whole process of the creation of snow from the very beginning began to be completely understood, there were some guesses about the "snow-white cover".
It all begins with the fact that under the influences of warm sunlight, water from rivers, lakes and seas turn into pairs, and rises high into atmospheric layers, where permafrost prevails. Couples, in turn, possessing properties liquid water, because of the high minus temperature begins to stick and turns into ice crystalline. These are snowflakes, which over time are ready to fall on the ground. For the most part, in those places where heat, ice floes fall out in the form of wet sediments, melted in the air.
How the snow is formed, now it is clear, but why, when falling to the ground, does he suddenly become white?
The question is appropriate, because the snowflakes are really still in the air have the same bandwidth properties of light through themselves as ice. But one should not forget one thing: the faces of the lens are located under chaotic angles, which randomly refracts the sunlight, and they do not absorb it, and they skip further. And when snowflakes are going to the "white bedspread", the rays of the sun, refraart from one snowflake to another, pass through the entire cover. Many rays are reflected in our eyes, which is why it is often when you look at the snow, you have to burst. Sunlight is too bright to perceive it not securely eyes.
But not quite correctly ask the question of why snow is white, because it is not always "clean." So see his people only when the rays of sunlight fall on it. For example, at sunset, it can be painted in a pinkish shade, and in the light of a yellow lantern can be slightly as well as in cloudy weather his shade is grayish.
Changes in the color of the snow also in the air layers, when snowflakes are just beginning their "Padenien Earth". For example, various pollen from trees and colors, dust with arid earth rises and occurs with snow grains in air flow. If such snow does not have time to melt and persists with a small cover, then its color will necessarily be with various shades. In these conditions, ask why snow is white, inappropriate.
However, snowflakes are not just flying chaotic ice floes, which for incomprehensible reasons decided to cover the ground with a "white bedspread".
The main properties of snow are to protect the ground from the cold, the covering of a thick bedspread. Yes, yes, it is to warm and preserve the crop and the soil from freezing, it would seem paradoxically, but it is true. It has a bad thermal conductivity, allowing it to restrain the heat coming out of the ground, and create a "heat pillow". No wonder the needle was built far North. Ice, like snow, keeps warm well, creating unique favorable conditions for life.
Do not lose sight of the fact that the size of the snowflake depends on weather conditions outside the window. If it is cold enough, then the ice floes are small, almost imperceptible. And if the sun shines and the air is not as cold, then the sizes of snowflakes can reach several centimeters. So, in 1944, decade-chantimetime "Crupes of Ice" fell out in Moscow.
In the thought of winter, there is always snow-white cover in imagination, which has enveloped everything around, while rarely who thinks over why it is white.
Water droplets that are in the atmosphere, at a minus temperature freeze and turn into ice, falling into the ground in the form of snow. The ice is water in a solid state, it is in itself transparent. Then why snow white?
Snowflakes also do not have colors, but if we consider them through a magnifying glass, it can be noted that they are similar to crystals that resemble the right hexagon with their faces. During snowfall, it is the verge of snowflakes that reflect light rays, give the snow familiar to us white.
On Earth, snow cover is a cluster of snowflakes, located very tightly to each other in chaotic order. All together they reflect light with greater powerSo even at night, when the surface is not illuminated by the sun, we see the snow white. The source of light rays at night is the moon, stars, lanterns.
However, the reason for the "whiteness" of the snow cover is not only in the ability of ice crystalline faces to reflect the light falling on them, and from the purity of their surface. The bottom line is that no snowflake can be perfectly transparent. In the atmosphere of water drops mix with different parts (dust, industrial emissions and other pollutants), which are able to absorb non-reflected rays of light.
Why does the snow shine?
In this case, the well-known law is valid: the incidence of the incidence is equal to the angle of reflection. Billions of microcrystals having the form of the right hexagon, absorb solar rays, refracted them, and then reflected in different directions and at different angles, like " sunny bunnies" Therefore, we see how snowflakes sparkle and shimmer into the sun.
Why are snowflakes under legs crunch and creak?
Walking through the snow, it is often possible to hear crunch or creak under your feet. Such a sound is obtained because snowflake crystals under mechanical pressure rub together and break. However, such a phenomenon can not be observed, but only at a certain temperature of the air.
The fact is that snow creaks only at temperatures from 2 to 20 degrees below zero, and at different temperature ranges, the creak and crunch are accompanied by a special sound. This is explained by the fact that in a strong frost, snowflakes are becoming more dense and strong, and at a temperature of 0 ° C and above, snow covers loses its strength and starts to melt.
In fact, even a breakdown of one small snowflake is accompanied by sound. But this sound is so weak that the human hearing organs simply do not perceive. At the time, trillions of snowflakes break, the sound becomes much stronger and the person clearly hears the characteristic crackling of the snow.
Marina Shkherina
Research project "Why snow white?"
The project is made in conjunction with the child.
Introduction
Winter came. On the street it became cold. White fluffy blanket covered all the earth, all trees. White snowflakes fall, fall on the ground, on the roofs of houses, on the trees, on people. Snowflakes look like white stars. They quietly fall to the ground.
I love to look at the snowflakes. They are very beautiful. As if lace, all different. Sometimes they stick together together and larger flakes fall to the ground. Sometimes the cold wind breaks white stars, turning them into small snow dust, and then it is very difficult to see them.
Once in the morning I woke up and looked out in the window. I saw that everything around: Earth, trees, roofs of houses, became white. It fell the first snow. I thought: "Why snow white?" And I decided to explore this problem.
This problem made it possible to formulate the topic of research: "Why is snow white?"
Deciding with the topic, set itself the goal: the study and conduct of experiments to answer the question "Why snow white?"
To achieve the goal, you need to solve the following tasks:
1. To explore the literature, which tells about the snow.
2. Prove the experimental way "Why snow white?"
3. To summarize the knowledge gained.
Object of study: snow.
Subject of study: Composition of snow
Hypothesis: Suppose that white snow color is associated with light reflection.
Research methods:
1. Study of literature on the topic
2. Observation of the object of research
3. Conduct experience
4. Analysis of the results and conclusions on the study
Chapter I. Theoretical Justification of Experimental Work.
1.1 What is snow?
What is snow? This is a lot, a lot of beautiful snowflakes; They fall and fall from height to the ground, on the trees, on the roofs of houses - clean, fragile, sparkling. And so he fell - this amazing snow. Located "magnificent carpets", white froth covered the Earth. The fallen snow fell asleep all the pits, ditches, compared the tubercles - completely transformed the plain. The forest was even more transformed. Snow scattered with white clams along the branches of trees, covered with a white blanket dropped on the ground leaves and bunches, lay down the high snowdrifts in shrubs. Attentive to the eye, he opened many secrets of forest life - everything that happened, imprinted on the snow cover, left the traces in the snow.
The meaning of the word "snow" I found in "modern explanatory dictionary" Snow is solid atmospheric precipitations consisting of small ice crystals dropping out of the clouds at temperatures below 0С. The snow is formed during the freezing of the water vapor contained in the atmosphere. Initially, tiny crystals appear. Following the air currents, they move in all directions. Gradually, crystalline "stick" to each other until hundredth or more are scored. When the dimensions of the frightened ice floes turn out to be quite large, they begin to fall to the ground. These clusters of ice floes we call snowflakes.
1.2 Where do snowflakes come from?
Snowflake is a frozen water crystal having a shape of a six-beam polyhedron.
Water couple rises high above the ground. The top is very cold, and ice cream is formed from it - crystalline. They are very small. It's not snowflakes. Falling down, crystalline rapidly increase. This is because there is a lot of water vapor in the air that settles on their surface and freezes. So the ice-crystalline becomes beautiful, tender snowflake.
Snowflakes are so many and all of them are different - there is not a single one.
The largest ever witnessed snowflake had a diameter of 12 cm. Usually, snowflakes have about 5 mm in diameter at a weight of 0.004.
Crystals from which snowflakes are in a definite form. This is either a six-pointed star, or a thin plate having a hexagon shape. The fact is that the main crystal of water has the form of the correct hexagon in the plane.
In 1885, American Farmer Wilson Bentley received the first successful photo of the snowflakes under a microscope. He was 46 years old and made more than 5,000 unique pictures. Based on its work, it was proved that there are no two identical snowflakes.
At different temperatures, crystals of various shapes are formed.
The most beautiful snowflakes fall there where the climate is severe - for example, in the north.
Depending on weather conditions in different places, "your" snow falls.
For the formation of large snowflake flakes, it is necessary to complete windlessness than longer snowflakes travel, the more faced and clips each other.
At low temperatures and strong winds, snowflakes face in the air, crumbling and falling to the ground in the form of fragments - "diamond dust".
1.3 Snowflake classification.
Prism There are 6-coal plates and thin columns with a 6-coal cross section. In prisms, tiny sizes, they are almost not visible to the naked eye. The verge of prisms, very often decorate various complex patterns.
Needles - Thin and long snow crystals, they are formed at a temperature of approximately -5 degrees.
When considering, they look like small bright hairs.
Dendriti - Or weaving, have pronounced branching thin rays. More often are large crystals, they can be seen with the naked eye. The maximum size of the dendrite can reach 30 cm in diameter.
12-ray snowflakes - Sometimes columns with tips are formed with a turn of plates relative to each other by 30 degrees. When rays grow from each plate, the crystal with 12 rays is obtained.
Hollow columns- Inside the columns with a hexagonal cross section, cavities are formed. Interestingly, the form of cavities is symmetrical relative to the center of the crystal. It is necessary to build a lot to consider the collapse in small snowflakes.
Fern dendrites - This type is one of the largest. The branches of star dendrites grow thin and very frequent, as a result, the snowflake begins to be like a fern.
Crystals of irregular shape- Snowy crystals are often small, asymmetric and frantic with each other. To get beautiful symmetric crystals, you need to be a good set of many weather circumstances.
Triangular crystals - Such snowflakes are formed at a temperature of about -2 degrees. In fact, it is hexagonal prisms, some of the sides of which are significantly shorter than others. But on the faces there may be rays.
Poulet sockets - Sometimes in the formation of crystals, they can grow and increase in random directions. Such formations are easily cleaned with separate crystals similar to bullets. Hence such an unusual name.
1.4 Why snow white?
When a Russian person is asked to imagine winter, he sees the first thing in his imagination snow, snow-white cover, which watched everything around. We are so accustomed to the snow color, that we do not even think why the snow is white. It turns out that all the colors perceived by us depend on the sun's rays. Black items completely absorb sunlight, so they are perceived by us black. And if the subject completely reflects the ray of the sun, then the color will seem white.
Snow is frozen water, and how we know, the ice is colorless. Why snow white? From the Internet and children's encyclopedia "everything about everything" I learned that the snowflakes are 95% consisting of air. Crystalline snowflakes are not smooth, but have faces. The reflection of light from the edges of these crystals makes snow white. The ice remains colorless, as the entire sunlight passes through itself. Yes, and each snowflake would have missed all the world and also did not have colors. But snowflakes usually fall on each other in a messy movement. And together they become opaque, but white. To figure out why snow is white, why he reflects the rays of the sun, we need to look at the composition of the snow. The snow is formed from snowflakes, and snowflakes from a huge amount of crystals. These crystals are not smooth, but with edges. This is the answer to our question, why the snow is white. It is from the edges that the sunlight is reflected. Water in the atmosphere is a pair, it freezes, and transparent crystals are formed. From the movement of the air, the crystals are freely moving up, then down. In this chaotic motion, crystals are connected to each other. And when, finally, too many crystals are going together, then they begin to fall on the ground already in the form of snowflakes usually. It turns out, the color of snow is white, because the light of the sun, which it reflects is white. Think if the sun beam became green or yellow, then the color of the snow was the same. Surely, many noticed that during sunrise or sunset, it seems to us that the rays of the sun become pinkish, so the snow at that moment see us pink.
Interesting Facts:
№1: Do you know that the snow is not always white? In many regions of the world, people had to see him red, green, blue and even black! The cause of such a variety of colors is tiny bacteria, fungi, as well as dust contained in the air and absorbed by snowflakes when they are lowered to the earth's surface.
Conclusion by I Chapter
1. I learned that snow is solid atmospheric precipitations consisting of small ice crystals.
2. Each snowflake is a totality of small ice floes.
3. The snow is formed from snowflakes, and snowflakes from a huge amount of crystals.
Chapter II. Organization of experimental work
on the problem "Why snow white?"
From his observations, studying literature, I learned that any snowflake has a shape of a six-pointed asterisk. Regardless of the shape of the snowflakes, they are all white. And the snow is white, and if the sun shines, it becomes dazzling white. Why? Snowflake consists of ice crystals and air, the light, falling on the rays of snowflakes, is reflected from them, dissipates and perceived by us as white. And when the sunbeam falls on the crystalline, he reflects from him and blind our eyes.
I decided to spend your experiences to prove that the snow is really white.
2.1 Holding experiments to answer the question "Why snow white?"
How I spent experiences
Experience number 1
I put the snow on a red cardboard, compared it with a white sheet of paper. Conclusion: snow white.
Experience number2
I took a transparent plastic bag. Cut it into small pieces. Each piece is "Snowflake". Mold all the pieces into a transparent glass. They settled in different ways.
Result: "Snow" in a white cup.
Experience number 3.
Poured water into the glass and put in the freezer. Water turned into a transparent ice. Mom smashed ice on small pieces. He became white.
Conclusion
Pieces polyethylene package And the pieces of ice separately transparent. The light passes through them and does not reflect. When pieces of the package are chaotic (differently, they reflect the light in different directions.
Output
Snow white, because each snowflake reflects the light in different directions. Scientific language - "light is dissipated." From this snow white.