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
2023-08-01
77
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/2887102.html
相关试题推荐
[originaltext]Qatarisspendingalmost$500millionaweekonmajorinfrast
[originaltext]Qatarisspendingalmost$500millionaweekonmajorinfrast
[originaltext]Qatarisspendingalmost$500millionaweekonmajorinfrast
[originaltext]W:WelcometoourTVshow,BookClub.Todaywearehonoredtohav
[originaltext]W:WelcometoourTVshow,BookClub.Todaywearehonoredtohav
[originaltext]W:WelcometoourTVshow,BookClub.Todaywearehonoredtohav
[originaltext]W:Hey,Mark.Inevernoticedthatbellyofyours.Whathaveyou
[originaltext]Onegoesdeepunderwaterandstarveshisbrainofoxygen.Ano
[originaltext]AnewstudysuggestsclimateconditionsintheSaharaDesert
[originaltext]AnewstudysuggestsclimateconditionsintheSaharaDesert
随机试题
Whatisbeingadvertised?[br][originaltext]Areyouinthemoodforsometh
WritingBasedonKnowledgeandExperienceDirections:Forthistask,
错
离子交换层析技术的主要原理是A.介质的分子筛作用 B.介质的吸附作用 C.介
患者于人工流产术过程中,突感胸闷,头晕。查:血压70/50mmHg,脉搏50次/
从所给的四个选项中,选择最合适的一个填入问号处,使之呈现一定的规律性: A.如
物业管理计划的主要内容包括()A:建筑物管理计划B:租赁计划C:财务收支计划
抗组胺药治疗荨麻疹用药注意事项与患者教育包括A.赛庚啶、酮替芬引起体重增加 B
某基金近3年的收益率分别为10%、12%、14%,则该基金3年 的几何平均收益
共用题干 男性,64岁。有肺心病史5年,经常头痛头晕,1周来咳嗽加重,咳黄痰,
最新回复
(
0
)