首页
登录
职称英语
【B1】 [br] 【B4】 [originaltext]A summary of the physical and chemical nature of li
【B1】 [br] 【B4】 [originaltext]A summary of the physical and chemical nature of li
游客
2024-03-04
58
管理
问题
【B1】 [br] 【B4】
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
releases
解析
转载请注明原文地址:https://tihaiku.com/zcyy/3503362.html
相关试题推荐
[originaltext]Ifyouvisitabigcityanywhereintheworld,youwillproba
[originaltext]Ifyouvisitabigcityanywhereintheworld,youwillproba
[originaltext]M:Hey,Karen.Youarenotreallyreadingit,areyou?W:Pardon?
[originaltext]M:Hey,Karen.Youarenotreallyreadingit,areyou?W:Pardon?
[originaltext]M:Hey,Karen.Youarenotreallyreadingit,areyou?W:Pardon?
[originaltext]W:Pleasehaveaseat,MrSuanders.Ireceivedyourresumelastw
[originaltext]W:Pleasehaveaseat,MrSuanders.Ireceivedyourresumelastw
[originaltext]Therearebetween3,000and6,000publiclanguagesinthewor
[originaltext]DeepSpringsisanAmericancollege.Itisanunusualcollege
[originaltext]DeepSpringsisanAmericancollege.Itisanunusualcollege
随机试题
Amotherandherseven-year-olddaughterwererestingintheirroominabighot
[originaltext]W:Tom,doyouhaveaminute?M:Oh,hi,Cathy,sure.Anything?W
A.accountB.acquiredC.basisD.certainlyE.counterpart
税金指国家税法规定的应计人建筑安装工程造价内的()等。A.营业税 B.城市维
正确的组合项目是A.滴虫阴道炎--米汤样白带 B.外阴阴道假丝酵母菌病--豆渣
清算退出的流程不包括()。A.清查公司财产、制订清算方案 B.依法宣告破
时下,垃圾分类已在多地落地生根。北京实施生活垃圾管理条例仅三个月,取得厨余垃圾分
城市道路一条车道的小汽车理论通行能力为每车道( )辆/h。A.1000 B.
工程项目的特性包括( )。 A.唯一性 B.固定性 C.可逆转性 D.
最新回复
(
0
)