"The Sun" PPT courseware 14

Description

"The Sun" PPT courseware 14

order of the sun

For humans, the glorious sun is undoubtedly the most important celestial body in the universe. The growth of all things depends on the sun. Without the sun, there would be no life phenomena in various forms on the earth, and of course there would be no human beings as intelligent creatures. The sun brings light and warmth to people, brings about the cycle of day, night and seasons, controls the changes in the earth's temperature and temperature, and provides various forms of energy for life on earth.

The sun, a planet that is both formidable and revered, is composed of what materials and what is its internal structure?

solar structure

Most of the materials that make up the sun are ordinary gases, of which hydrogen accounts for about 71%, helium accounts for about 27%, and other elements account for 2%. From the center outward, the sun can be divided into nuclear reaction zone, radiation zone, convection zone, and solar atmosphere. The sun's atmosphere can be divided into three layers according to different heights and different properties, namely the photosphere, the chromosphere and the corona. Although the core area of ​​the sun is very small, with a radius only 1/4 of the sun's radius, it is the real source of the sun's huge energy. The temperature is extremely high, reaching 15 million degrees Celsius, and the pressure is also extremely high, causing the heat to fuse hydrogen into helium. Nuclear reactions can occur, releasing enormous amounts of energy. This energy is then transferred to the bottom of the solar photosphere through the transfer of matter in the radiative layer and troposphere, and is radiated outward through the photosphere.

The mystery of the sun’s temperature!

In daily life, the farther away from the heat source, the lower the temperature. However, the situation in the solar atmosphere is completely opposite. The temperature at the top of the photosphere near the chromosphere is almost 4300°C. At the top of the chromosphere, the temperature is as high as tens of thousands of degrees. , in the coronal region the temperature suddenly rises to millions of degrees. People are puzzled by this abnormal warming phenomenon, and the exact cause has not yet been found.

sun movement

There are intense activities in the atmosphere of the photosphere. With a telescope, you can see that there are many densely packed spot-like structures on the surface of the photosphere, which look like rice grains, called rice grains. It is currently believed that this rice grain structure is a phenomenon caused by the violent convection of gas under the photosphere. Another famous activity on the surface of the photosphere is sunspots. Sunspots are huge airflow vortices on the photosphere. Most of them are nearly elliptical. They appear dark against the bright photosphere background. But in fact, their temperature is as high as about 4000°C. If the sunspots can be taken out individually, a large sunspot would be It can emit light equivalent to the full moon. The appearance of sunspots on the sun's surface is constantly changing, and this change reflects changes in solar radiation energy. There is a complex periodic phenomenon in the changes of sunspots. The average activity period is 11.2 years.

source of solar energy

Before this century, scientists were unable to explain the source of solar energy. It was not until the development of nuclear physics that scientists got a satisfactory answer. At high temperatures, all atoms dissociate into positively charged nuclei and negatively charged electrons; due to the high temperature of the sun, the atomic nuclei fuse, and the mass lost in mutual fusion is converted into energy. According to Einstein's theory of mass-energy interconversion: energy is equal to mass multiplied by the square of the speed of light. The mass lost during nuclear fusion is very small, but it can be converted into a large amount of energy, so the source of solar energy is nuclear fusion.

Keywords: Sun teaching courseware, E-education edition sixth grade science PPT courseware download for the second volume, sixth grade science slide courseware download, Sun PPT courseware download, .PPT format;

For more information about "The Sun" PPT courseware, please click on the "Sun ppt" tab.

"The Cosmic Environment of the Earth" The Earth in the Universe PPT (The influence of the sun on the earth in the second lesson):

"The Cosmic Environment of the Earth" The Earth in the Universe PPT (The Influence of the Sun on the Earth in the Second Lesson) Part One: Strengthening the Implementation of Basic Knowledge [ Key Points for Self-Reading Textbooks] 1. The Effect of Solar Radiation on the Earth The impact of 1. Overview of the Sun (1) Shape: Huge blazing gas...

Two cartoon rainbow sun PPT background pictures:

These are two cartoon rainbow sun PPT background pictures. The background elements include: rainbow, white clouds, clouds, and cartoon sun. .PNG format;..

"The Influence of the Sun on the Earth" Earth in the Universe PPT courseware:

"The Influence of the Sun on the Earth" Earth in the Universe PPT courseware Part One Contents: Course Standard Explanation 1. Analyze the data, explain the main impact of solar radiation on the earth, and understand that conventional energy sources such as coal and oil are solar energy fixed by organisms in geological history. (Comprehensive thinking) 2...

File Info

Update Time: 2024-10-06

This template belongs to science courseware E-education edition sixth grade science volume 2 industry PPT template

Preview