中间图

Or
icon
OG20官方指南,建议同学们刷3遍。第一遍做题了解题型和考点,第二遍精刷,第三遍集中解决疑难问题。建议考生第一遍刷题采用官方正版纸质书籍,若遇到疑难问题,欢迎在此专区查阅解析,提供解析,参与题目讨论,与所有考生一起解决疑难问题。
阅读RC-15429 (第4/4题) Time Cost00:00
收藏
该题平均耗时:1m54s,平均正确率:30.1%

建议使用官方纸质指南,查看对照完整题目

When asteroids collide, some collisions cause an asteroid to spin faster others slow it down. If asteroids are all monoliths---single rocks---undergoing random collisions, a graph of their rotation rates should show a bell-shaped distribution with statistical "tails" of very fast and very slow rotators. If asteroids are rubble piles, however, the tail representing the very fast rotators would be missing, because any loose aggregate spinning faster than once every few hours (depending on the asteroid's bulk density) would fly apart. Researchers have discovered that all but five observed asteroids obey a strict limit on rate of rotation. The exceptions are all smaller than 200 meters in diameter, with an abrupt cutoff for asteroids larger than that.

The evident conclusion---that asteroids larger than 200 meters across are multicomponent structures or rubble piles---agrees with recent computer modeling of collisions, which also finds a transition at that diameter. A collision can blast a large asteroid to bits, but after the collision those bits will usually move slower than their mutual escape velocity. Over several hours, gravity will reassemble all but the fastest pieces into a rubble pile. Because collisions among asteroids are relatively frequent, most large bodies have already suffered this fate. Conversely, most small asteroids should be monolithic,because impact fragments easily escape their feeble gravity.

【OG20-P459-606题】

The author of the passage mentions "escape velocity" in order to help explain which of the following?

  • 分析A选项
    xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
  • 分析B选项
    xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
  • 分析C选项
    xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
  • 分析D选项
    xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
  • 分析E选项
    xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
该题目由网友7PEz6Ph提供。更多GMAT题目请
暂无雷哥网文字解析
当前版本由 百香果蜂蜜茶 更新于2017-08-09 17:02:11 感谢由 百香果蜂蜜茶 对此题目的解答所做出的贡献。

解题思路:定位在第二段绿色高亮的部分。原文说,速度变慢,后来被reassemble,即,为了说明大的小行星在撞击之后,如何保持,选e


A 没有说行星会变小而不是变大

B 不是在说再聚合的速度

C 不是在说撞击的频率

D 不是为了说明直径小于200的行星转速

E 正确



题目讨论 10条评论)

用户头像
提交
  • 用户头像

    Seeyouth

    A. The tendency for asteroids to become smaller rather than larger over time
    This answer gives general info of what happens after a collision. But it does not refer to escape velocity. Hence wrong answer.
    
    B. The speed with which impact fragments reassemble when they do not escape an asteroid's gravitational attraction after a collision
    This seems correct. But there is flaw. Escape velocity is speed of the asteroid above which bits may move outside. It is not the speed which impacts reassemble. Hence wrong answer.
    
    C. The frequency with which collisions among asteroids occur
    Out of scope. There is no discussions regarding frequency of collisions.
    
    D. The rotation rates of asteroids smaller than 200 meters in diameter
    There is no info regarding rotation rates in this context. Hence wrong answer.
    
    E. The tendency for large asteroids to persist after collisions
    If the bits moved FASTER than their mutual escape velocity, then the bits would "escape" from each other and the large asteroid would remain blown to bits.
    However, if the bits move SLOWER than their mutual escape velocity, the bits will not escape from each other and, instead, will reassemble due to gravity. Thus, after being blown to bits, most of the bits of the large asteroid will reassemble, explaining the tendency for large asteroids to persist after collisions. (E) is the correct choice.
    1 0 回复 2021-08-17 01:07:32
  • 用户头像

    217523uujb

    A. The tendency for asteroids to become smaller rather than larger over time
    This answer gives general info of what happens after a collision. But it does not refer to escape velocity. Hence wrong answer.
    B. The speed with which impact fragments reassemble when they do not escape an asteroid's gravitational attraction after a collision
    This seems correct. But there is flaw. Escape velocity is speed of the asteroid above which bits may move outside. It is not the speed which impacts reassemble. Hence wrong answer.
    C. The frequency with which collisions among asteroids occur
    Out of scope. There is no discussions regarding frequency of collisions.
    D. The rotation rates of asteroids smaller than 200 meters in diameter
    There is no info regarding rotation rates in this context. Hence wrong answer.

    E. The tendency for large asteroids to persist after collisions
    If the bits moved FASTER than their mutual escape velocity, then the bits would "escape" from each other and the large asteroid would remain blown to bits.
    However, if the bits move SLOWER than their mutual escape velocity, the bits will not escape from each other and, instead, will reassemble due to gravity. Thus, after being blown to bits, most of the bits of the large asteroid will reassemble, explaining the tendency for large asteroids to persist after collisions. (E) is the correct choice.

    0 0 回复 2021-01-09 23:42:01
  • 用户头像

    Mariposa爱学习

    Over several hours, gravity will reassemble all but the fastest pieces into a rubble pile. Because collisions among asteroids are relatively frequent, most large bodies have already suffered this fate.
    仔细读这句话,感受作者想说什么
    大行星被撞击变成碎片,撞击后碎片移动慢,最后引力把它们整合,飞的最快的碎片会变成碎石堆,很多大行星都遭受了这个命运
    所以作者想说的是很多大行星也是经历了撞击了,现在也还都在
    0 0 回复 2020-11-14 17:19:03
  • 用户头像

    571661zxzq

    文章没有讲reassemble(聚合) 的速度,讲的是collision之后,bits 的速度小于escape velocity的速度,导致了gravity reassemble them to rubble piles。这里从来没有提及reassemble的速度到底是多少,而且escape velocity 不等同于reassemble的速度,所以b选项:The speed with which impact fragments reassemble= impact fragments reassemble with the speed 是错的。
    0 0 回复 2020-08-04 08:40:06
  • 用户头像

    288327yjof

    原文不是还说了速度快的不会被reassemble 吗,那这样不就回越来越小了?
    0 0 回复 2019-12-12 11:37:21
    • 评论用户头像

      Carmen678回复 288327yjof

      这题不是推理题,如果问你文中的statement能得出什么结论的话这选项就行,但是这里是问作用,作者提到这个点是为了说明什么,这个是要在文中找的,也就是要在这个点之后的地方找作者的目的

      0 0 回复 2020-01-01 16:50:18

    • 评论用户头像

      175115uybpy回复288327yjof

      我也是这样想的……直接自信选A了……

      0 0 回复 2020-11-22 18:45:12

    • 评论用户头像

      旮旮回复288327yjof

      原文说的是gravity resemble,而不是speed

      0 0 回复 2021-10-30 11:02:39

  • 用户头像

    冲鸭750

    After  collision
    0 0 回复 2019-01-30 19:59:14
  • 用户头像

    1123

    这个题问的是escape velocity帮助解释了什么,而不是说EV其本身是什么。那么,结合关键词前后的句子得知,一些bits通常会移动的比较慢,因此几个小时之后,地球引力就会重组所有移动得慢的bits成为rubble pile,也就是large asteroids。这就是选项large asteroids persists的改写。
    0 0 回复 2018-11-21 11:18:03
    • 评论用户头像

      194888hphm回复1123

      这应该说的不是地球的引力,应该是小行星自身的引力

      0 0 回复 2020-07-08 13:46:03

  • 用户头像

    ZoeyYoung

    B.仔细读B. The speed (with which) impact fragment reassemble when they do not escape an asteroid's gravitational attraction after a collision.这是在说受影响的碎片聚合在一起并不在逃离重力吸引力的速度,也就是聚合速度,但文章中并没有提到这一点,只是提到这些小块状不会再分离了,并没有说道下一步聚合。聚合这个过程是在下一句中才提到
    E.文章中问的是escape velocity在原文中的作用,那么看这个句子,说明的是撞击后‘those bits will usually move slower than their mutual escape velocity.’所以这里的escape velocity想说的是这些小块状比escape velocity慢,趋于稳定,也就是E选项。
    0 0 回复 2018-09-06 13:00:30
  • 用户头像

    Chongdi

    上句大概意思是小行星炸成了bits,下句是用小行星的gravity把bits给reassemble起来,那这句就应该是保持,逻辑是炸出bits——bits保持——再把bits重组回来。B就错在“重组的速度”,人家明明在保持,下句才重组,B就开始说重组的速度了。
    1 0 回复 2018-09-06 10:53:31
  • 用户头像

    考到770不是梦

    虽然这个速度确实和c的意思有点关系,但是毕竟是个专有名词。如果作者想让选c,那么他一定会在后面解释,既然文中没有解释这个词。说明作者提这个强调的是整句话。整句话的内容是:rubble撞击之后会变成bits,bits的速度比这个速度小。是一种趋势,符合e的说法。
    0 0 回复 2018-07-16 12:44:44
    • 评论用户头像

      考到770不是梦回复考到770不是梦

      打错了,是b不是c【。

      0 0 回复 2018-07-16 12:45:09

  • 手机注册
  • 邮箱注册
登录>







关闭图标

标题图

  • 图标

    知识库学习

    GMAT语法、逻辑、阅读、数学各单项备考知识点学习及测验
  • 图标

    在线做题

    包含GMAT各单项必考知识点题目、OG/PREP/GWD/雷哥讲义题目、难度650/680/700/730题库题目练习及题目解析
  • 图标

    在线模考

    语文套题/数学套题/全套仿真模考,包含GWD/PERP/精选模考等上百套套题模考
  • 图标

    在线测评

    适合5种不同基础的GMAT学员,测评后可自动出具分数报告及复习计划指导
  • 图标

    资料下载

    GMAT必备备考资料下载、鸡精下载、课程课件等免费下载
  • 图标

    课程学习

    注册会员后,可在GMAT课程区,选择免费直播课程及公开课程进行在线学习
×
请你选择你要查看的模考成绩单
立即开通 暂不开通
加载图片
网络异常