Question 2: What is the shape of the earth? The earth is not a standard regular sphere, but an irregular sphere with slightly flat poles and slightly bulging equator.
/kloc-at the end of 0/7, Newton, a great British scientist, studied the influence of the earth's rotation on the shape of the earth. He speculated theoretically that the earth is not a very round sphere, but an ellipsoid with slightly raised equator and slightly flattened poles, and the equatorial radius is more than 20 kilometers longer than the polar radius. From 1735 to 1744, the French Academy of Sciences sent two survey teams to conduct arc surveys in northern Europe and South America respectively, and the survey results confirmed that the earth was indeed an ellipsoid. If you look at it from a distance, you will find that the earth is shaped like a pear: its equatorial part protrudes and is its "pear body"; The North Pole is a bit sharp, like "pear pedicle"; The South Pole is a little concave, like a "pear navel", and the whole earth is like a pear-shaped rotator, so people call it a "pear-shaped earth".
Question 3: What is the shape and size of the earth, teaching material analysis?
This section is the first lesson of learning geography knowledge, which plays a great role in forming students' methods of learning geography and understanding the geographical content of geography learning. Stimulate students' interest in learning geography through the discussion in the preface. In the subsequent study of specific knowledge, we should also follow this goal, and change geographical knowledge from difficult to easy, to easy and interesting, and to something that students are interested in and easy to accept.
Teaching objectives
1. By understanding the process of human understanding of the earth and feeling the spirit of predecessors' courage to explore, it is clear that human understanding of nature also has a process, and everyone shoulders the heavy responsibility of continuing to explore.
2. From a mathematical point of view, learn to explain the size of the earth with relevant data.
capability goal
Understand the process of human understanding the shape of the earth through pictures and videos, learn to feel the shape of the earth in connection with reality, and look for clues that are difficult to find in life to prove the true shape of the earth.
Curriculum standard requirements
Provide evidence that the earth is a sphere.
● Describe the size of the earth with average radius, equatorial circumference and surface area.
Emphasis and difficulty in teaching
Key point: the size of the earth.
Difficulty: understanding the shape of the earth
teaching method
Use facts to guide students to observe geographical phenomena from life, and to understand and explore the laws of the existence and development of geographical things.
training/teaching aid
Multimedia-aided courseware
teaching process
Before class: [Welcome screen] Self-made welcome screen: world map and a little girl's head and welcome words: Welcome to the geography knowledge hall! For the students who just entered geography, it is very important to create an academic atmosphere for learning geography. Use words and girls' heads to make the atmosphere serious and cordial. They felt respect and inspired their desire to love and learn geography. )
Students: Welcome to our geography knowledge hall! Are you qualified to be an earthman? (The teacher said kindly, with on-screen text animation)
[Survey of Qualified Earthlings]: (According to the classroom content, design 1 ~ 5 related questions according to real life, and introduce the teaching while investigating students, and the underlined part is the contact content)
1. What shapes do you observe for the sun, moon and stars?
2. When you were young, did you ever think about the question "What is the shape of the earth"? ?
What shape do you think the earth is now? Can you cite relevant facts to illustrate?
4. How to describe the size of basketball with data? What about the size of the earth?
These questions can be answered by students or discussed by everyone. The process of answering is a process of conversation, a process of communication between teachers and students, a process of discussion among students, and a process of sublimation from life to science. Let students realize that geography knowledge comes from life, and geography learns geography in life.
Question 1: The sun is round. A little extension can lead to the conclusion that the sun is spherical. The moon looks different at different times and shapes, but it is actually a sphere. As for why it is different, some students may say that it doesn't matter if they don't. Tell them we'll study it later; Stars are dot-shaped, but actually spherical, but they are reduced to dots because they are too far away from us. ...
Question 2: Tell the truth and encourage students to observe and think more.
Question 3: Sphere, the students already know. Why? Different students get this concept from different channels, which can be said at will. The key point is to stimulate interest and improve students' sense of participation.
Follow-up: What do you think the earth is like if you only observe phenomena? Bang ... the ancients had the same idea as you. Scholars in different regions and stages have put forward different opinions on the shape of the earth. Let's learn about people's exploration of the shape of the earth through a short film.
[Video clip] The process of human understanding the shape of the earth (without video, you can also refer to the textbook "The Process of Human Understanding the Shape of the Earth")
Extended summary: Is there any evidence that the earth is a sphere? Can the two examples in the textbook P3-4 prove that the earth is a sphere?
1. Sailing at sea ── The earth is not flat, climb high and look far ─── The earth is not flat.
2. Eclipse-The earth is round, too.
Magellan's voyage around the world-confirmed that the earth is a sphere.
4. Satellite photos of the earth-confirming that the earth is a sphere.
Students read Magellan's Sailing Around the World. According to people's exploration of the shape of the earth, please talk about your feelings: express your views and guide students to understand the following.
● Science is accumulated through people's continuous exploration. The truth that is considered correct today may be overthrown tomorrow, so we should believe in science, but don't be superstitious about books ... >>
Question 4: What does the earth look like from the air? Video Potato/Program/View /ggkcwpzuddc/ Do you think it is feasible?
Question 5: 3 billion years ago, the earth was like this. Humans have no way of knowing what the earth was like 3 billion years ago. If there is such a video, it is also imaginary.
Question 6: I want to make an animated video. Not that kind of album video. But has its own design action shape. For example, there is an earth in the video. Zoom in slowly. There should be a design process in pre-production, that is, lens splitting. As long as there is a sketch, you should draw it yourself. Specifically, Baidu is how animation content develops, similar to a script with pictures. Then, it is to make 3d, model with 3dmax or maya, and then set the action of the model. There are tutorials online. If it is 2d, it should be drawn frame by frame, and then each short animation can be synthesized by ae or pr, which can be added. Some special effects ae are mainly effects, such as lens movement, smoke effect, pr is mainly editing, and then adding sound to the audio track with pr is basically completed, right?
Question 7: What is the earth like? The earth is round, so are other planets. The water drops we see are also round in the air. Bubbles are also round.
Due to the surface tension of liquid, bubbles and water droplets are round.
Why the earth is round begins with the birth of the earth. The original universe was a high-density substance with high temperature and high energy. Because of the big bang, all kinds of planets were produced. At that moment, those planets were all liquid at high temperature, and they were all round because of surface tension. After hundreds of billions of years of cooling, the temperature on the surface of some stars gradually decreased, and then the protein gradually came into being, which gave birth to life. This planet is the earth.
Question 8: 1, what is the earth like? The earth is one of the eight planets in the solar system, ranking the third in the order from near to far from the sun, and the earth-like planet with the largest diameter, mass and density in the solar system, with a distance of10.50 billion kilometers from the sun. The earth rotates from west to east and revolves around the sun at the same time. At present, there is a natural satellite-the moon, which forms a celestial system-the earth-moon system. It originated from the primitive solar nebula 4.6 billion years ago.
The equatorial radius of the earth is 6378. 137km, the polar radius is 6356.752km, the average radius is about 637 1km, and the equatorial circumference is about 40076km. It is an irregular elliptical sphere with slightly flat equator and slightly protruding poles. The surface area of the earth is 5 1 100 million square kilometers, of which 7 1% is ocean and 29% is land. Seen from space, the earth looks blue.
There are core, mantle and shell structures inside the earth, and hydrosphere, atmosphere and magnetic field outside the earth. The earth is the only known celestial body with life in the universe at present, and it is the home of millions of creatures, including human beings.
Land-sea distribution
The total area of the earth is about 5,654.38+0,007.2 million kilometers, of which land accounts for 29.2% (6,543.8+48.94 million kilometers) and the rest 70.8% (3,665.438+0.32 million kilometers) is water. The land is mainly in the northern hemisphere, with five continents such as Europe and Asia, Africa, America, Australia and Antarctica, and there are many islands. The oceans include the Pacific Ocean, the Atlantic Ocean, the Indian Ocean, the Arctic Ocean, the Southern Glacial Ocean and their affiliated sea areas. The coastline is * * * 356,000 kilometers.
Extreme altitude
Lowest land point: Dead Sea -4 18m.
The lowest point in the world: Mariana Trench-11.034m.
The highest point in the world: Mount Everest, 8844.43 meters.
Question 9: What is the shape of the earth? An oval sphere with slightly convex equator and slightly flat poles.
Question 10: What will the future earth look like? If we follow the laws of nature, 1. Temperature: The earth is currently in an interglacial period. As for whether the temperature will drop to the ice age or continue to rise to the highest point, since the birth of the earth, the ice age and interglacial period have changed back and forth rather than have any laws to follow. Or we haven't observed its changing law yet. Geology: The earth was originally a collection of interstellar dust, and gradually developed into a sphere with a core, a mantle and a crust. Magma under the crust flows over the mantle, for example, the seabed of the expanding plate in the middle of the Pacific Ocean stretches to both sides, and then it will be squeezed by the rocks under the crust, making the plate stretch. As a result, the Eurasian plate and the American plate continue to separate (which explains why all the continents were connected to form Pan-continent in the beginning). On the seabed of some coasts, the plates will sink, making the geological strata in a constant cycle. Therefore, these plates should be further separated from each other in the future. The above is only my personal speculation and does not represent a scientific point of view.