“Exercise for the mind” in geography.
6th grade.
Task No. 1
1. He was the first to suggest that the Earth is spherical:
A. Aristotle B. Pythagoras C. Ptolemy
2. The first expedition around the world was made by:
A. Christopher Columbus B. Ferdinand Magellan C. Vasco da Gamma
3. Distribute the continents as their sizes decrease:
1. South America 2. Eurasia 3. Africa
4. Australia 5. North America 6. Antarctica
4. Arrange objects according to their geographical location from west to east:
A. Sahara Desert B. Atlantic Ocean C. Andes G. o. New Zealand
5. The Prime Meridian passes through the city:
A. London B. Paris C. Berlin D. Moscow
6. The eastern edge of the continent of Eurasia is washed by:
A. Indian Ocean B. Pacific Ocean C. Atlantic Ocean D. Arctic Ocean
Task No. 2
On the map, the distance from Tokyo to Beijing is 30 cm; on the ground, this distance is 1500 km. Determine the scale of the map.
Task No. 3
Which trip around the world is shorter?
A) along the 60th parallel or along the equator?
B) along the 60th meridian or along the 30th meridian?
Prove your answer.
Task No. 4
Arrange the maps according to the degree of enlargement of their scale:
A. 1: 200,000 B. 1:100,000 C. 1:500,0000 D. 1:1000,0000
Task No. 5
Points A and B are in the eastern hemisphere. Point A is on the 20th, and point B is on the 40th meridian. Which one is located further west?
Task No. 6
Geographical task.
An oil driller, a scuba diver, a polar explorer and a penguin argued - who is closer to the center of the Earth?
The scuba diver says: “I will sit in the submersible and go down into the Mariana Trench, its depth is 11022 m and I will find myself closer to the center of the Earth.”
The polar explorer says: “I will come to the North Pole and will be closest to the center of the Earth.”
Driller: “I will drill a well to a depth of 14 km and will be closest to the center of the Earth.”
The penguin doesn't say anything, he just lives in Antarctica.
It is known that the height of the continent of Antarctica is 3 km + the height of the ice sheet is 3-4 km.
Arrange the heroes of the task as the distance to the center of the Earth increases.
Task No. 7
Uranus revolves around the Sun, lying on its side (that is, the axis of rotation is parallel to the ecliptic plane). Does there be a change of seasons on Uranus?
Who said the earth is round? December 17th, 2014
They say that this is...
However, the hypothesis that our planet is spherical has existed for a very long time. The first to express this idea back in the 6th century BC was the ancient Greek philosopher and mathematician Pythagoras. Another philosopher, Aristotle, who lived in Ancient Greece two centuries later, provided visual evidence of sphericity: after all, during lunar eclipses, the Earth casts a precisely round shadow on the Moon!
Gradually, the idea that the Earth is a ball hanging in space and not supported by anything spread more and more widely. Centuries have passed, people have long known that the Earth is not flat and does not rest on whales or elephants... We walked around the world, crossed our ball in literally all directions, flew around it on an airplane, photographed it from space. We even know why not only ours, but also all other planets, the Sun, the stars, the Moon, and other large satellites are “round” and not some other shape. After all, they are large and have enormous mass. Their own gravitational force - gravity - tends to give celestial bodies a spherical shape.
Even if some force, greater than gravity, appeared, which would give the Earth the shape of, say, a suitcase, the end would still be the same: as soon as the action of this force ceased, the force of gravity would begin to collect the Earth again into a ball, “pulling in” protruding parts until all points on the surface are at an equal distance from the center.
Let's continue thinking about this topic...
Not a ball!
Back in the 17th century, the famous physicist and mathematician Newton made a bold assumption that the Earth is not a ball, or rather, not quite a ball. He assumed it and proved it mathematically.
Newton “drilled” (mentally, of course!) two communicating channels to the center of the planet: one from the North Pole, the other from the equator, and “filled” them with water. Calculations showed that the water settled at different levels. After all, in a polar well, only the force of gravity acts on the water, but in an equatorial well, it is also opposed by centrifugal force. The scientist argued: in order for both columns of water to exert the same pressure on the center of the Earth, that is, for them to have equal weight, the water level in the equatorial well should be higher - according to Newton’s calculations, by 1/230 of the average radius of the planet. In other words, the distance from the center to the equator is greater than to the pole.
To check Newton's calculations, the Paris Academy of Sciences sent two expeditions in 1735 - 1737: to Peru and Lapland. The expedition members had to measure meridian arcs - 1 degree each: one - in equatorial latitudes, in Peru, the other - in polar latitudes, in Lapland. After processing the expedition data, the head of the northern expedition, geodesist Pierre-Louis Maupertuis, announced that Newton was right: the Earth is compressed at the poles! This discovery of Maupertuis was immortalized by Voltaire in... an epigram:
Envoy of physics, brave sailor,
Having overcome both mountains and seas.
Dragging the quadrant among the snow and swamps,
Almost turning into a Lapp.
You found out after many losses.
What Newton knew without walking out the door.
It was in vain that Voltaire was so sarcastic: how can science exist without experimental confirmation of its theories?!
Be that as it may, now we know for sure that the Earth is flattened at the poles (if you like, stretched out at the equator). It is stretched, however, quite a bit: the polar radius is 6357 km, and the equatorial radius is 6378 km, only 21 km more.
Does it look like a pear?
However, is it possible to call the Earth, if not a ball, but an “oblate” ball, namely an ellipsoid of rotation? After all, as we know, its relief is uneven: there are mountains, there are also depressions. In addition, it is affected by the gravitational forces of other celestial bodies, primarily the Sun and the Moon. Even if their influence is small, the Moon is still capable of bending the shape of the liquid shell of the Earth - the World Ocean - by several meters, creating ebbs and flows. This means that the radii of “rotation” are different at different points!
In addition, in the north there is a “liquid” ocean, and in the south there is a “solid” continent covered with ice - Antarctica. It turns out that the Earth does not have a completely regular shape, it resembles a pear extended towards the North Pole. And by and large, its surface is so complex that it does not lend itself to a strict mathematical description. Therefore, scientists have proposed a special name for the shape of the Earth - geoid. The geoid is an irregular stereometric figure. Its surface approximately coincides with the surface of the World Ocean and continues on the mainland. The same “height above sea level” that is indicated in atlases and dictionaries is measured precisely from this geoid surface.
Well, scientifically:
Geoid(from ancient Greek γῆ - Earth and other Greek εἶδος - view, literally “something like the Earth”) - a convex closed surface that coincides with the surface of water in the seas and oceans in a calm state and perpendicular to the direction of gravity at any point. A geometric body deviating from a figure of rotation. An ellipsoid of revolution and reflecting the properties of the gravity potential on the Earth (near the Earth's surface), an important concept in geodesy.
1. The world's oceans
2. Earth's ellipsoid
3. Plumb lines
4. Body of the Earth
5. Geoid
The geoid is defined as the equipotential surface of the earth's gravity field (level surface), approximately coinciding with the average water level of the World Ocean in an undisturbed state and conditionally extended under the continents. The difference between the actual mean sea level and the geoid can reach 1 m.
By definition of an equipotential surface, the surface of the geoid is perpendicular to the plumb line everywhere.
A geoid is not a geoid!
To be completely honest, it is worth admitting that due to differences in temperature in different parts of the planet and the salinity of the oceans and seas, atmospheric pressure and other factors, the surface of the water surface does not even coincide in shape with the geoid, but has deviations. For example, at the latitude of the Panama Canal, the difference in levels between the Pacific and Atlantic oceans is 62 cm.
Strong earthquakes also affect the shape of the Earth. One of these magnitude 9 earthquakes occurred on December 26, 2004 in Southeast Asia, in Sumatra. University of Milan professors Roberto Sabadini and Giorgio Dalla Via believe that it left a “scar” on the planet’s gravitational field, causing the geoid to bend significantly. To test this assumption, the Europeans intend to send into orbit a new GOCE satellite, equipped with modern highly sensitive equipment. We hope that he will soon send us accurate information about what shape the Earth has today.
In the endless expanses of space there are billions of star clusters - galaxies, among them the Milky Way galaxy. Inside this galaxy is our solar system with a bright star at the center, around which 9 planets revolve. The third planet of this star, called the Sun, is our Earth, which is more than a million times smaller than the Sun.
How was the Earth formed?
- The formation of the Sun began when a nebula - a giant cloud of cosmic gases and dust - began to shrink under the influence of gravity. The remains of a cloud of hot gases and dust revolved around the newborn Sun.
- Gradually, large clumps were formed from colliding dust particles, which, under the influence of gravitational forces, connected with each other into protoplanets. One of them became the Earth. In the center of this huge rotating hot ball, heavy elements were concentrated - iron and nickel.
- Lighter metals and compounds rose to the surface of the ball. As they cooled, a hard, dense outer shell formed.
- Naz rose from the surface of the young planet, forming an atmosphere and clouds. The rains falling from these clouds filled the depressions in the earth's crust with moisture, forming oceans. It was in water that the first organisms producing oxygen appeared.
- As a result of these long-term transformations, the present appearance of the Earth was formed, but our planet continues to change.
Why is the Earth Unique?
Unlike the other 8 planets in the solar system, Earth has water and the atmosphere contains oxygen. It is thanks to this that life can exist on Earth.
Who proved that the Earth is round?
For thousands of years, people believed that the Earth was flat. But in 1519-1522. The Spanish expedition, led by the Portuguese navigator Ferdinand Magellan (died in 1521, the voyage was completed by Juan Sebastian de Elcano on the only surviving ship "Victoria"), made a historical trip around the world, circumnavigating the globe. This proved once and for all that the Earth is round.
Who is Copernicus?
Until the 16th century most people believed that the sun and planets revolved around the earth. In 1543, the work “On the Revolutions of the Celestial Spheres” was published, in which his auto-Polish astronomer Nicolaus Copernicus (1473-1543) proved that the Earth rotates around its axis and, together with the other planets, revolves around the Sun. Copernicus' teachings refuted church dogmas, and from 1616 to 1828 his book was banned by the Catholic Church.
How long does it take for the Earth to revolve around the Sun?
Our planet makes a full revolution around the Sun in 365.25 days, or one year. The Earth also rotates around its axis, which runs from the North Pole to the South Pole. The Earth makes a complete revolution around itself in 24 hours, or one day.
Online lesson on the world around us “Shape of the Earth.” Each of you knows that our planet Earth is round, like a ball. Although, most likely, it is a slightly flattened ball, or rather a geoid. And this ball moves in outer space...
So, a long time ago, people were sure that the Earth was a flat circle that lay in the middle of a boundless ocean. In ancient India, it was believed that the Earth was held up by four elephants, and the elephants stood on a huge turtle.
The ancient Greeks believed that the Earth has the shape of a convex disk, which is washed on all sides by the Ocean River. A copper firmament stretches above the Earth, along which the Sun moves, rising and plunging daily into the waters of the Ocean.
The Greek astronomer Ptolemy tried to explain and prove to people that the Earth is spherical, but no one believed him.
Over time, people began to travel a lot. They traded in different countries, that is, they exchanged products and products that they had in abundance for those that they lacked. Hunters exchanged animal skins for swords and knives, for strong metal vessels; farmers gave bread for fabrics, beautiful bracelets and necklaces. Such traders were called merchants. They went on trips both by land and by sea - on small ships.
The first sea travelers were warned that the Earth was flat and at its edge the World Ocean fell into the abyss like a huge waterfall. A ship that sails to the edge of the Earth will fall into the abyss and die.
Long journeys helped people get to know the Earth more and better. Maps of the earth's surface have appeared, although they are still far from complete and accurate.
It was the travelers who were able to prove that the Earth is spherical... Although, people could not believe that the Earth is a ball. “Let’s say the Earth is spherical,” they reasoned. - But when the ship descends from its top and moves to the lower regions of the globe, it will be impossible for it to climb back up the mountain!
So, five proofs that the Earth is spherical.
First proof. The great Portuguese traveler Ferdinand Magellan made the world's first trip around the world, thereby proving that the Earth is round. Having gone east to the spice islands, he returned home from the other side, from the west...
The journey was difficult. Of the 5 ships (256 people crewed), two ships returned home, with only 20 people on board. Magellan himself died during a battle with the aborigines on one of the islands.
Second proof. Horizon. This is the border between heaven and earth. Watching through a telescope, sea travelers could not understand why ships on the horizon were not immediately visible as a whole, but in parts?
Who will see the approaching ship first: the one standing on the shore, or the one at the lighthouse?…. What does this mean?
Lost in the forest, a man climbed a tree, why?... What does this mean?
Third proof. People have been observing the moon for a long time. The Moon is a natural satellite of the Earth. This is a huge stone ball. Remember that the moon does not shine itself, it is illuminated by the sun. In addition, the moon takes on a new look every time. Why?
That's right, the Moon rotates with the Earth around the Sun. And the Sun illuminates the Moon from different directions. At that time, the Earth blocks the Moon from sunlight.
Now look carefully, what is the shadow of the Earth on the Moon? ... Exactly, round!
Fourth proof. Earth from space. When Yuri Gagarin first went into space, he also made a round-the-world trip around the Earth, but in outer space. What did Yuri Gagarin see from the porthole while admiring the beauty of planet Earth?
Would you like to fly around our planet like Yuri Gagarin? No problem! An interesting video made using time-lapse photography from the International Space Station. Lights of big cities, white flashes of lightning... Are you flying?
The debate about who said that the Earth is round continues today. There are still individuals who are trying to prove that the Earth is flat, even ignoring images of the globe in photographs from space. So, the round shape of the Earth has been known since ancient times.
Who was the first to say that the Earth is round?
Once upon a time, many thousands of years ago, people believed that the Earth was flat. In the myths of different peoples, in the works of ancient scientists, it was stated that the Earth rests on three whales, on elephants and even on a huge turtle. Let's try to figure out who said that the Earth is round.
The ancient Greek scientist Parmenides, who lived approximately 540-480. BC e., in his philosophical poem “On Nature” he wrote that the Earth is round. This was a revolutionary conclusion about the shape of the planet, but it cannot be unequivocally assumed that Parmenides was the first to express this idea. The scientist wrote about the round shape of the Earth in the section “Opinions of Mortals,” where he described the thoughts and ideas of his contemporaries, but not his conclusions. A contemporary of Parmenides was Pythagoras of Samos.
Pythagoras, together with his students, studied the theory of universal and cosmic harmony. It was in the records of adherents of the Pythagorean school that many thoughts were found that the flat Earth could not be in harmony with the celestial sphere. To the question: “Who said that the Earth is round?” Pythagoras himself most likely answered, formulating the idea of the earthly sphere as the most suitable, according to the theories of geometry and mathematics.
Scientists who declared the shape of the Earth
Which scientist said that the Earth is round? In addition to Parmenides and Pythagoras, there were other ancient thinkers who studied the Earth and space. Today, any schoolchild knows the principle of the “sundial”, when during the day sticks on the sand cast shadows of different lengths and at different angles. If the earth were flat, either the length of the shadows or the angle between the object and the shadow would not change. However, in ancient times, only serious scientists paid attention to such details of existence.
Thus, the philosopher from Alexandria Eratosthenes of Cyrene, who lived in the 3rd-2nd centuries. BC e., made calculations on the day of the summer solstice, using the difference between the shadows of objects, the zenith and the angle between them. He even managed to calculate the approximate size of our planet and is considered the first researcher to describe the concepts of modern longitude and latitude, since in his calculations he used data from different geographical places of Alexandria and Siena.
Later, the Greek Stoic philosopher Posidonius in 135-51. BC e. also calculated the dimensions of the globe, but they turned out smaller for him than for Eratosthenes. So today it is quite difficult to unequivocally answer the question of who was the first to say that the Earth is round.
Aristotle on the Earth
The Greek scientist, thinker, philosopher Aristotle said that the Earth is round back in the 4th century BC. e. He not only put forward hypotheses and made rough calculations, but also collected evidence that the Earth is spherical.
Firstly, the scientist notices that if you look from the shore at a ship that is approaching the observer, then first the mast becomes visible from the horizon, then the hull of the ship itself. Such evidence convinced very few.
Secondly, its more significant proof is based on observations of lunar eclipses. As a result, Aristotle concluded that the Earth has the shape of a sphere, because the shadow of the Earth on the surface of the Moon did not change during eclipses, that is, it was always round, which only a ball gives.
Thirdly, during his trip to Egypt, Aristotle, observing the sky, described in detail the changes in constellations and stars in the Southern and Northern Hemispheres. He wrote: “... stars are observed in Egypt and Cyprus that were not seen in the northern regions.” Such changes can only be seen from a round surface. Moreover, the scientist concluded that the Earth’s sphere is small in size, since changes in the stars and terrain can only be determined from a fairly limited surface.
First star map
And who was the first to say that the Earth is round, in the East? An unusual story is the caliph Al-Mamun, who lived in the 7th century, to whom Aristotle and his students once appeared in a dream. The scientist showed Mamun the “image of the Earth.” Based on the images he saw, Mamun reproduced the “star map,” which was the first map of the Earth and planets in the Islamic world.
Mamun ordered the court astronomers to measure the size of the Earth, and the circumference of the planet they obtained, equal to 18,000 miles, turned out to be quite accurate: the length of the Earth's equator calculated to date is about 25,000 miles.
World sphere
Thus, by the 13th century the idea of the round shape of the Earth was already firmly established in science. The famous English mathematician, founder of the decimal number system, John de Sacrobosco, or John of Halifax, as he is called in England, published his famous treatise “On the World Sphere.” In this work, Sacrobosco summarized the conclusions of Eastern astronomers and the ideas of Ptolemy's Almagest. Since 1240, the World Sphere has become the main textbook on astronomy at Oxford, the Sorbonne and other prestigious universities around the world and has gone through about 60 editions over 400 years.
Christopher Columbus picked up the baton of the idea of a world sphere when he began his famous voyage to India in 1492, sailing from Spain to the west. He was sure that he would reach the continent, because the Earth has a spherical shape, and it doesn’t really matter which way to swim: anyway, the movement will be closed in a circle. So it is no coincidence that Columbus was the first to prove that the Earth is round, as they say in many modern textbooks. He was an educated, enterprising, but not very successful navigator, since all the glory of the discoverer went to his colleague Amerigo Vespucci.
Biblical Descriptions of the Earth
In the Bible, information about the system of celestial bodies and the shape of the Earth actually looks somewhat contradictory. Thus, in some Old Testament books the flat shape of the earth and the geocentric model of the world are quite clearly described:
(Psalm 103:5) “Thou hast set the earth on firm foundations: it shall not be shaken for ever and ever”;
Book of Ecclesiastes (Ecc. 1:5) “The sun rises, and the sun sets, and hastens to its place where it rises”;
Book of Joshua (Joshua 10:12) “...stand, O sun, over Gibeon, and the moon, over the valley of Aijalon!”
But still she spins!
The Bible also says that the Earth is round, and some interpretations of Holy Scripture confirm the heliocentric structure of the world:
Book of the prophet Isaiah, 40:22: “He is the One who sits above the globe of the Earth...”;
Book of Job (Job 26:7): “He (God) stretched out the north over the void, hung the Earth on nothing”;
(Job 26:10): “He drew a line over the surface of the water, to the borders of light and darkness.”
The benefits and harms of the Inquisition
Such ambiguity in the biblical images of the Earth, the Sun and other celestial bodies can really be explained by the fact that Holy Scripture was not intended to reveal the physical structure of the Universe, but was intended to serve only the salvation of the human soul. However, in the Middle Ages, the church, being the forefront of science, was forced to search for the truth. And she had to either compromise with the theories of various scientists or prohibit them from scientific activity, since it was not possible to combine the conclusions they received with some biblical interpretations, as well as with the dominant theory of Aristotle - Ptolemy at that time.
Thus, Galileo Galilei (1564-1642) was recognized as a heretic for his active propaganda of the heliocentric system of the world, substantiated at the beginning of the 16th century by Nicolaus Copernicus (1473-1543). The most scandalous and sad act of the Inquisition - the burning at the stake of Giordano Bruno in 1600 - is known to any schoolchild. True, in fact, the verdict of the Inquisition in the case of the monk Bruno Nolanz had nothing to do with his reasoning about the heliocentric system of celestial bodies; he was accused of denying basic Christian dogmas. However, the persistence of this myth speaks of the deep importance of the works of astronomers for modern science and religion.
Does the Koran say that the Earth is round?
Since the Prophet Muhammad was one of the later founders of the monotheistic religion, the Koran absorbed the most advanced ideas of science and religion, based on the colossal treasures of knowledge of the learned men of the East. This holy book also contains evidence for the round shape of the Earth.
"He covers the day with night, which quickly follows."
"He entwines the night in the day and entwines the day in the night."
Such continuous cyclicity and uniform overlap of day and night clearly indicates the sphericity of the Earth. And the verb “wraps around” is absolutely unambiguously used, emphasizing the circular motion of the luminary around the globe of the Earth.
"No and no! I swear by the Lord of the East and West! Verily, We are able."
Obviously, on a flat Earth there can only be one west and one east, and only on a round Earth there can be many of them. The position of the west and east changes relative to the horizon due to the rotation of the Earth.
“A sign for them is the dead land, which We revived and brought from it grain on which they eat” (36:33)
And another quote from the Koran:
“The sun floats to its abode. This is the decree of the Mighty, the Knowing. We have predetermined positions for the moon until it again becomes like an old palm branch. The sun does not have to catch up with the moon, and the night does not run ahead of the day. Everyone floats in orbit” (36:38-40).
Also in the Holy Book of Muslims there is a unique verse with the words “After that He spread out the earth” (79:30), where a special Arabic verb “da-ha” was used, which has two meanings: “to spread” and “to round.” This very figuratively emphasizes that from the top the earth seems to be spread out, while it has a rounded shape.
To new discoveries
Our planet with all the legends, myths, tales, theories and evidence about it is still of scientific, social and religious interest today. No one can claim that the planet has been fully studied; it conceals a great many mysteries, and future generations will have to make many of the most incredible discoveries.