首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
A new kind of radar has been developed for space-age travelers. A working laboratory model of a new system of radar that makes u
A new kind of radar has been developed for space-age travelers. A working laboratory model of a new system of radar that makes u
admin
2014-04-23
21
问题
A new kind of radar has been developed for space-age travelers. A working laboratory model of a new system of radar that makes use of a beam of light is said to be ten thousand times more accurate than the best comparable system of radar that uses microwaves.
The model has shown that this radar system (known as laser-doppler radar) can measure with absolute precision speeds varying from spaceship orbital injection velocities (速度) of five miles per second down to virtual stops—speeds of less than one ten thousandth of an inch per second. According to the scientists who are developing this system, such fine measures of velocity are of prime importance in space missions. In a rendezvous (会合, 会合点) between two spaceships, or in a landing approach by a vehicle onto an orbiting space station, a bump could rip open a ship’s skin, or a nudge (轻触) could knock the station out of its orbit.
The light-beam radar, which operates at a frequency of trillions of cycles per second, could easily detect and measure the movement of a vehicle edging up to a satellite space station even at a small fraction of an inch per second. A control system using so precise a signal as this would allow a huge vehicle to dock at a space station as lightly as a feather.
This selection could be entitled______.
选项
A、The Function of Radar
B、Problems in Space Navigation
C、Radar for the Space Age
D、Space Stations
答案
C
解析
文中第一句是主题句,也是解答这道要旨题的依据。主题句说:“一种新的雷达已经为太空时代的旅行者开发出来了。”文中的其他句子都是围绕这个主题句而展开的。故选项C与主题句的含义相符合。
转载请注明原文地址:https://kaotiyun.com/show/hoWO777K
0
在职攻硕英语联考
相关试题推荐
Thesinglegreatestshiftinthehistoryofmass-communicationtechnologyoccurredinthe15thcenturyandwaswelldescribedby
Theex-presidenthadbeen______inthecountrytorefreshhismindbeforehepassedaway.
Currentdatasuggestthat,although______statesbetweenfearandaggressionexist,fearandaggressionareasdistinctphysiolo
ThehistoryofresponsestotheworkoftheartistSandroBotticelli(1444—1510)suggeststhatwidespreadappreciationbycritics
By1830theformerSpanishandPortuguesecolonieshadbecomeindependentnations.Theroughly20million【C1】______ofthesenati
Mostepisodesofabsent-mindedness—forgettingwhereyouleftsomethingorwonderingwhyyoujustenteredaroom—arecausedbya
Mostepisodesofabsent-mindedness—forgettingwhereyouleftsomethingorwonderingwhyyoujustenteredaroom—arecausedbya
Whenyouthinkofthetremendoustechnologicalprogresswehavemade,it’samazinghowlittlewehavedevelopedinotherrespect
ThePonyExpressisanoutstandingexampleofcourage,endurance,anddeterminationinthewestwardexpansionoftheUnitedStat
ThePonyExpressisanoutstandingexampleofcourage,endurance,anddeterminationinthewestwardexpansionoftheUnitedStat
随机试题
下列与脑性瘫痪不符的表现是
下列除哪项外均为呃逆的治疗原则
A.30日B.6个月C.3年D.5年《药品生产许可证》的许可事项发生变更的,提出变更申请应在变更前
一次死亡(遇险)3~9人各类事故发生后要在()小时内逐级报告至国家安全生产监督管理总局调度统计机构。
关于聚光型灯具,下列说法正确的有()。
某市有两种品牌的出租车,分别是大众和奇瑞,经调查发现:市场上营运的出租车中有60%是大众,剩下40%是奇瑞,大众出租车发生车祸的平均概率是3%,奇瑞则为4%。现在该市发生了一起出租车车祸,则()。
根据材料回答下列问题。2010年某地区上半年期末职工人数248573人,同比增长11.9%。其中:企业226917人,比重占91.3%,同比增长13.1%;事业单位15380人,负增长6.6%;机关5071人,增长3.3%。可以看到,企业职工人数比重大,
下列咏花的诗句中,属于咏梅花的是()①宁可枝头报香死,何曾吹落北风中②忽然一夜清香发,散作乾坤万里春③雪满山中高士卧,月明林下美人来④疏影横斜水清浅,暗香浮动月黄昏
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:
Therocketengine,withitssteadyroarlikethatofawaterfallorathunderstorm,isanimpressivesymbolofthenewspaceage
最新回复
(
0
)