首页
登录
职称英语
【B1】 [br] 【B6】 [originaltext]A summary of the physical and chemical nature of li
【B1】 [br] 【B6】 [originaltext]A summary of the physical and chemical nature of li
游客
2023-08-01
15
管理
问题
【B1】 [br] 【B6】
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
radiation
解析
转载请注明原文地址:https://www.tihaiku.com/zcyy/2887104.html
相关试题推荐
【B1】[br]【B9】[originaltext]Eversincethebreakingofthe"ironbowl"inC
【B1】[br]【B5】[originaltext]Eversincethebreakingofthe"ironbowl"inC
【B1】[br]【B3】[originaltext]Eversincethebreakingofthe"ironbowl"inC
【B1】[br]【B2】[originaltext]Eversincethebreakingofthe"ironbowl"inC
[originaltext]Thecompetitionamongproducersofpersonalcomputersisesse
[originaltext]Thecompetitionamongproducersofpersonalcomputersisesse
[originaltext]Manyuniversitystudentsdislikestudyinghistorybecausethe
[originaltext]Manyuniversitystudentsdislikestudyinghistorybecausethe
[originaltext]WhenWalterwaseightyearsold,in1908,heusedtoworkfor
[originaltext]WhenWalterwaseightyearsold,in1908,heusedtoworkfor
随机试题
WhichAttributesofaFoodProductareMostImportanttoConsumersA)Th
当代国际储备的显著特点是()A.国际储备外汇化 B.结构管理标准化 C.外
隧道风速风向检测器的风向测量精度不应该超过()。A.±3° B.±5° C.
下列哪项不属于医学伦理原则A.不伤害原则 B.公正原则 C.有利原则 D.
下面是人教版义务教育数学教科书七年级上册的内容,据此回答下列问题。 两辆汽车从
中性粒细胞比例不增多的情况是A.脾功能亢进 B.败血症 C.女性月经期 D
1995-90.柴胡在四逆散中的配伍意义是A.疏散透表B.解肌清热C.疏肝解
一住店客人未付房钱即想离开旅馆去车站。旅馆服务员揪住他不让走,并打报警电话。客人
固定义齿修复中,基牙倾斜角度较大时,可采用以下设计获得共同就位道,除外A.改良3
安全生产许可证颁发管理机关或者其上级行政机关可以撤销已经颁发的安全生产许可证的情
最新回复
(
0
)