首页
财务会计
医药卫生
金融经济
考公考编
外语考试
学历提升
职称考试
建筑工程
IT考试
其他
登录
职称考试
Black Holes 1 Black holes can be best described as a sort of vacuum, suckin...
Black Holes 1 Black holes can be best described as a sort of vacuum, suckin...
admin
2020-12-24
11
问题
Black Holes
1 Black holes can be best described as a sort of vacuum, sucking up everything in space. Scientists have discovered that black holes come from explosion of huge stars. Stars that are near death can no longer burn due to loss of fuel, and because its temperature can
no longer control the gravitational (重力的)force, hydrogen ends up putting pressure onto the star’s surface until it suddenly explode then collapses.
2 Black holes come from stars that are made of hydrogen, other gases and a few metals. When these explode it can turn into a stellar-mass (恒星质量) black hole, which can only occur if the star is large enough (should be bigger than the sun ) for the explosion to break it into pieces, and the gravity starts to compact every piece into the tiniest particle. Try to see and compare: if a star that’s ten times the size of the sun ends up being a black hole that’s no longer than 70 kilometers, then the Earth would become a black hole that’s only a fraction of an inch!
3 Objects that get sucked in a black hole will always remain there, never to break free. But remember that black holes can only gobble up (吞噬) objects within a specific distance to it. It’s possible for a large star near the sun to become a black hole, but the sun will continue to stay in place. Orbits (轨道) do not change because the newly formed black hole contains exactly the same amount of mass as when it was a star, only this time its mass is totally contracted that it can end up as no bigger than a state.
4 So far, astronomers have figured out that black holes exist because of Albert Einstein’s theory of relativity. In the end, through numerous studies, they have discovered that black holes truly exist. Since black holes trap light and do not give off light, it is nearly impossible to detect black holes via a telescope. But astronomers continue to study galaxies (银河系), space and the solar system to understand how black holes might evolve. It is possible that black holes can exist for millions of years, and later contribute to a bigger process in galaxies, which can eventually lead to creation of new entities (实体). Scientists also credit black holes as helpful in learning how galaxies began to form.
A newly formed black hole and the star it comes from are of _____________
选项
A the tiniest particle
B a fraction of an inch
C the same amount of mass
D an explosion of huge stars
E the creation of new entities
F the existence of black holes
答案
C
解析
第三段第四句 "Orbits (轨道)do not change because the newly formed black hole contains exactly the same amount of mass as when it was a star”,意思是“新形成的黑洞的轨道不会变,因为它的质量和它之前是恒星时的质量一样”。所以答案是C,“相同的质量”。
转载请注明原文地址:https://ti.zuoweng.com/ti/pxsQKKKQ
相关试题推荐
Thearticlesketchedthemajoreventsofthedecade.AdescribedBofferedCoutl
Thearticlesketchedthemajoreventsofthedecade.AdescribedBofferedCoutl
Thearticlesketchedthemajoreventsofthedecade.AdescribedBofferedCoutl
Marydrewahouseonthepaper.A:depicted B:designedC:described D:portrayed
BlackHoles 1Blackholescanbebestdescribedasasortofvacuum,suckin...
BlackHoles 1Blackholescanbebestdescribedasasortofvacuum,suckin...
BlackHoles 1Blackholescanbebestdescribedasasortofvacuum,suckin...
BlackHoles 1Blackholescanbebestdescribedasasortofvacuum,sucking...
BlackHoles 1Blackholescanbebestdescribedasasortofvacuum,sucking...
BlackHoles 1Blackholescanbebestdescribedasasortofvacuum,sucking...
随机试题
机体发生创伤后,营养状况的评估指标中不包括的是( )。 A、血小板测定 B
(2017年)下列各项中,导致企业留存收益发生增减变动的有( )。
()是从观察到的资料出发,加以概括,从而解释事物之问的联系,是由经验上升为
碘是人体必需的元素,但是统一在食盐中添加碘的方式可能导致“补碘”过量。某些非缺碘地区增售无碘盐,人们可以根据具体情况自主调节摄碘量。该材料体现的哲理有()。A
关于检査胎位四步触诊法的描述,下列哪项是错误的A用以了解子宫的大小,胎先露,胎方位B第一步,双手置于宫底部,了解宫底髙度,并判断是胎头还是胎臀C第二步
来自同一总体的两样本,下列哪个指标小的样本均数估计总体均数时更可靠A:B:CVC:SD:t0.05,v·SE:
在项目进度管理中,工作时间估计的准确性主要依赖于()。A:对项目的质量要求B:项目范围定义C:对项目工作了解程度D:可参考的历史经验E:工作人员的个人经
项目评估的投资估算方法是()。A:参照类似项目套算B:综合估算C:逐项估算D:指标估算
通过面状布孔灌浆,改善岩基的力学性能,减少基础的变形,以减少基础开挖深度的一种灌浆方法是()。A.固结灌浆B.帷幕灌浆C.接触灌浆D.高压喷射灌浆
隧道喷锚暗挖施工前,应核对地质资料,调查沿线()等,并制定保护措施。A.地质构造B.地下构筑物C.地下管线D.地面建筑物基础E.地下水分布现状