How the sphere is formed 100

Round Earth.

Not only is the Earth round, almost all planets are round. This is the law of the universe.

The star formed by the condensation of the nebula--- the early days of the earth was just an asteroid, relying on gravity to continuously capture foreign celestial bodies to strengthen themselves, and the alien celestial bodies are moving at a high speed relative to the earth, so the process of capture is a violent collision. The tremendous energy of the collision caused it to melt into liquid. At this time, the Earth is weightless in space, and the forces are equal in each direction under the gravitational and molecular gravitational forces.

Therefore the liquid substance will become the standard circle. Because only a circle can minimize the gravitational potential energy of each particle. This is the principle of energy minimum.

Because of this, the gravitational differentiation of the Earth's interior (heavy matter sinks to the core, light matter floats on the surface) gives the Earth a circle structure.

Today, scientists on the space station use the method of melting steel to cool in the air to make steel balls, because there is no gravity, the extruded molten steel floats in the air, and the force is equal in each direction under the gravitational pull of atoms and molecules. So it condenses into a flawless ball. Its precision is unattainable with any machining on the earth's surface.

As for the mountains and oceans on the Earth's surface, they are caused by extraterrestrial impacts and plate movements after the Earth cools and solidifies.

Imagine if the Earth's surface today was full of oceans and the Earth did not rotate (the centrifugal force of rotation causes the equator to bulge and the poles to concave to the poles). It should be a standard ball.

The ball can be rolled, it's as simple as that. Why is gravity pulling so far?

The set of all points whose distance to a spatial point p(x,y,z) is less than the constant r.

Then you should look at the New Dialectics of Nature, why all celestial bodies are round.

The main features of the sphere:

1. The distance from any point on the sphere to the center of the sphere is equal to the radius.

2. The cross-section of the ball is a circle.

3. Three-dimensional graphics with and only one continuous surface.

4. The orthographic projection on any plane is a circle of equal size, and the diameter of the projection circle is equal to the diameter of the sphere.

5. The line between the center of the sphere and the center of the cross-section circle is perpendicular to the cross-section.

6. The distance d from the center of the sphere to the cross-section has the following relationship with the radius r of the ball and the radius r of the cross-section: r 2 = r 2-d 2.

There is no such thing as a perfect sphere in reality

Whether it is a circle or a sphere, there is no real perfect "circle" in this world, and when we magnify seemingly perfect round objects to a thousand or even ten thousand times, we will find that the surface of these objects is actually pitted, and the perfect circle does not exist at all.

Previously, scientists from the United States, Germany, Japan and other precision industry countries have joined forces to create the world's only perfect sphere that is claimed to be the closest to a circle. This seemingly ordinary metal sphere is made of silicon-28, and it took scientists five years and 15 million yuan to complete it in order to pursue the ultimate perfection.

The original intention of manufacturing this sphere is actually very simple, at that time, the international use of kilogram containers made of platinum-iridium alloy, that is to say, we often call weights, because the relationship between the time and the song has been worn out, the quality has also been deviated, and in order to create a brand-new, accurate weight to reach the international level, the most perfect sphere was born.

According to reports, this sphere, which is less than the size of a palm, has consumed a total of 25 orders of magnitude.

In order to ensure the purity of the atoms, scientists used nuclear power plants.

centrifuge for purification. The surface is polished with an ultra-precision polishing machine, and in the process of grinding, scientists also need to consider problems such as thermal expansion and cold contraction.

Although the most perfect sphere is no longer more than 1 in 30 million from the center at any point on its surface, and its workmanship has reached its extreme state, the sphere is still flawed. The defect that scientists respond to in a round object is pi.

It is decided, just as one cannot count the following decimal places, as long as it cannot be calculated to the end, a truly perfect circle cannot exist.

The main features of the sphere:

1. The distance from any point on the sphere to the center of the sphere is equal to the radius.

2. The cross-section of the ball is a circle.

3. Three-dimensional graphics with and only one continuous surface.

4. The orthographic projection on any plane is a circle of equal size, and the diameter of the projection circle is equal to the diameter of the segment with the imaginary sphere.

5. The line between the center of the sphere and the center of the cross-section circle is perpendicular to the cross-section.

6. The distance d from the center of the sphere to the cross-section has the following relationship with the radius r of the ball and the radius r of the cross-section: r 2 = r 2-d 2.

The cross-section of the ball has the following properties:

1. The line between the center of the sphere and the center of the cross-section circle is perpendicular to the cross-section.

2. The distance d from the center of the sphere to the cross-section has the following relationship with the radius r of the ball and the radius r of the cross-section: r 2 = r 2-d 2.

The circle that is truncated by the plane of the sphere that passes through the center of the ball is called a great circle, and the circle that is truncated by the section that does not pass through the center of the sphere is called a small circle.

On a sphere, the length of the shortest line between two points is the length of the inferior arc between these two points of the great circle passing through these two points.

The characteristics of the sphere are:1. The distance from any point on the spherical surface to the center of the ball is equal to the radius.

2. The cross-section of the ball is a circle.

3. Three-dimensional graphics with and only one continuous surface.

4. The orthographic projection on any plane is a circle of equal size, and the diameter of the projection circle is equal to the diameter of the sphere.

5. The connection between the center of the sphere and the center of the cross-sectional circle is straight to the cross-section.

6. The distance d from the center of the sphere to the cross-section has the following relationship with the radius r of the ball and the radius r of the cross-section: r 2 = r 2-d 2.

Formula for the surface area of the ball:Let the radius of the ball be $r$, and the surface area of the ball is uniquely determined by the radius $r$, so its surface area $s$ is based on $r$ as the independent variable.

i.e. $s sphere = 4 r 2$.

The volume formula of the ball:v ball = rac r 3$ ($r$ is the radius of the ball).

Features:

A sphere is a three-dimensional figure with a continuous surface, and the geometry enclosed by the sphere is called a sphere.

There is no absolute sphere in the world. Absolute spheres exist only in theory.

But in a weightless environment, such as space, the droplets automatically form absolute spheres.

Spherical properties. Use a plane to cut a ball, and the cross-section is a circular surface. The cross-section of the ball has the following properties:

1. The line between the center of the sphere and the center of the cross-section circle is perpendicular to the cross-section.

2. The distance d from the center of the sphere to the cross-section has the following relationship with the radius r of the ball and the radius r of the cross-section: r 2 = r 2-d 2.

The circle in which the sphere is cut by the plane of the toucher in the center of the bright potato sphere is called the great circle, and the circle that is truncated by the cross-section that does not pass through the center of the sphere is called the small circle.

On a sphere, the length of the shortest line between two points is the length of a bad arc between these two points of the great circle passing through these two points, and we call this arc length the spherical distance between the two points.

1. Dirty spheres.

Dirty, a Chinese word, is pronounced āng zāng, which means dirty, unclean.

2. Shiny spheres.

Shiny, a Chinese word, pronounced shǎn liàng, means to shine brightly, brightly and luminously.

3. The Orb of Terror.

Terror, pronounced kǒngbù, is a Chinese word meaning to threaten, intimidate. Fear caused by a threat to a life or seeing a violent, bloody scene.

4. Tiny spheres.

渺小 is a Chinese word, pinyin miǎo xiǎo, which is interpreted as very small or completely insignificant, and often refers to something that is more humble and insignificant than anything of the same kind; Or it refers to a despicable personality.

5. Crystal spheres.

Jingying is a Chinese word, pronounced jīng yíng, which describes light and transparent, mostly referring to spherical objects such as dewdrops.

Dirty orbs Shiny orbs Scary orbs Tiny orbs ...

Crystal Sphere Beautiful Sphere.

What is the sphere and what is it???

Table tennis, rattan ball, shuttlecock, billiards, bow, cricket, squash ball, mothball, roller, watermelon, longan, lychee, coconut, orange, grape, dandelion, cactus, marbles, leather balls, balloons, rubber balls, glutinous rice balls, candy, lollipops, etc.

The geometry of space formed by a semicircle rotating around the straight line where the diameter is located is called a sphere, referred to as a sphere, and the radius of the semicircle is the radius of the sphere. A sphere is a three-dimensional figure with and only one continuous surface, and this continuous surface is called a sphere. The orthographic projection of a sphere on any one plane is a circle of equal size, and the diameter of the projected circle is equal to the diameter of the sphere.

At any point on the surface of the sphere, the distance to the center of the sphere is equal.

1. The straight line where the diameter of the semicircle is located is called the axis of rotation, and the rotating body formed by the rotation of the semicircle surface is called a sphere, referred to as a sphere.

1) The center of a semicircle is called the center of the sphere. (2) The radius of the semicircle is called the radius of the ball. (3) The diameter of the semicircle is called the diameter of the ball.

2. Representation of the ball: It is represented by letters that indicate the center of the ball, such as ball O.

1.The projection is circular in either direction.

2.The distance from the center to the surface is equal.