首页
登录
职称英语
【B1】 [br] 【B2】 [originaltext]A summary of the physical and chemical nature of li
【B1】 [br] 【B2】 [originaltext]A summary of the physical and chemical nature of li
游客
2024-03-04
30
管理
问题
【B1】 [br] 【B2】
A summary of the physical and chemical nature of life must begin, not on the Earth, but in the Sun. In fact, it is at the Sun’s very center. It is here that is to be found the source of the energy that the Sun constantly pours out into space as light and heat. This energy is liberated at the center of the Sun as billions upon billions of nuclei of hydrogen atoms collide with each other and fuse together to form nuclei of helium(氦). And, in doing so, it releases some of the energy that is stored in the nuclei of atoms. The output of light and heat of the Sun requires that some 600 million tons of hydrogen be converted into helium in the Sun every second. This the Sun has been doing for several thousands of millions of years.
The nuclear energy is released at the Sun’s center as high-energy gamma radiation, a form of electro-magnetic radiation like light and radio waves, only of very much shorter wavelength. This gamma radiation is absorbed by atoms inside the Sun, to be re-emitted at slightly longer wavelengths. This radiation, in its turn, is absorbed and re-emitted. As the energy filters through the layers of the solar interior, it passes through the X-ray part of the spectrum(频谱), eventually becoming light. At this stage, it has reached what we call: the solar surface and can escape into space, without being absorbed further by solar atoms. A very small fraction of the Sun’s light and heat is emitted in such directions that after passing through space, it hits the Earth.
选项
答案
Constantly
解析
转载请注明原文地址:https://tihaiku.com/zcyy/3503360.html
相关试题推荐
[originaltext]W:Jason,actuallyI’mgoingtoEnglandthissummer.M:Really?
[originaltext]I’dliketolookatavitalaspectofe-commerce,andthatis
[originaltext]I’dliketolookatavitalaspectofe-commerce,andthatis
[originaltext]Moderator:Hello,ladiesandgentlemen.Itgivesmegreat
[originaltext]Moderator:Hello,ladiesandgentlemen.Itgivesmegreat
[originaltext]Moderator:Hello,ladiesandgentlemen.Itgivesmegreat
[originaltext]Moderator:Hello,ladiesandgentlemen.Itgivesmegreat
[originaltext]Passwordsareimportant.Youremployer,yourbankandyoursm
[originaltext]Passwordsareimportant.Youremployer,yourbankandyoursm
[originaltext]Whenitcomestosuccessintheschoolenvironment,whatare
随机试题
Itistruethattheworldfacesproblemsofpollution,butitcan______(通过全球的努力加
Whatisthemostimportantfunctionoflanguage?A、Interpersonal.B、Informative.
Thearrestofamanforallegedlypostingapictureofaburningpoppy(Peopl
Revit提供的创建地形表面的方式有()。A.放置点 B.通过导入创建 C.
休克患者动态监测中心静脉压2.45kPa(25cmHO),表示A.肺梗死 B
下列哪种疾病不是由于营养过剩引起的( )。A.佝偻病 B.肥胖 C.糖尿病
下列各句中,加点的成语使用恰当的一项是()。A. B. C. D.
社会中心课程理论的以()为代表。
为严明纪律,树立公安队伍良好形象,公安部于2003年1月22日发布了加强公安机关
构建信用社会,提升社会文明 在今天,无论是投资置业、贷款理财,还是市场交易
最新回复
(
0
)