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
49
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.
Laser-doppler radar makes use of______.
选项
A、light
B、microwaves
C、sound waves
D、both A and B
答案
A
解析
这是一道综合理解题。文中第一段第二句说:“据说,一种采用光束的新型雷达系统的实验工作模型比采用微波技术最优的同类雷达系统要准确万倍。”在第二段第一句中说:“模型已经显出这种雷达系统(命名为激光多普勒雷达)能够绝对准确地测量速度变量,从太空飞船每秒五英里的发射速度到实际静止的每秒小于一万分之一英寸的速度。”综合以上内容,我们得知多普勒激光雷达系统是使用光束的。所以A是正确答案。
转载请注明原文地址:https://www.kaotiyun.com/show/FoWO777K
0
在职攻硕英语联考
相关试题推荐
Forlaymenethnologyisprobablythemostinterestingofthebiologicalsciencesfortheveryreasonthatitconcernsanimalsin
Thisvillagewhichissurroundedbymountainsisonly______byriver,anditisobviousthatthetransportationisinconvenient.
AtleastsincetheIndustrialRevolution,genderroleshavebeeninastateoftransition.Asaresult,culturalscriptsaboutm
Ithaslongbeenknownthattotalsleep______is100percentfataltorats,yet,uponexaminationofthedeadbodies,theanimals
Marriedpeoplelive"happilyeverafter"infairytales,buttheydosolessandlessofteninreallife.I,likemanyofmyfri
Wearepreparedtosatisfyallyour______claims.
Assumingthataconstanttravel-timebudget,geographicconstraintsandshort-terminfrastructureconstraintspersistasfundame
Whatdotheextraordinarilysuccessfulcompanieshaveincommon?Tofindout,welookedforoperations.Weknowthatcorrelation
PresidentCoolidge’sstatement,“ThebusinessofAmericaisbusiness,”stillpointstoanimportanttruthtodaythatbusinessin
Withitscommoninterestinlawbreakingbutitsimmenserangeofsubject-matterandwidely-varyingmethodsoftreatment,thecri
随机试题
代表被保险人购买保险,从保险人处取得佣金的保险中介人是()
判断休克患者微循环状况较可靠的依据是
A、正中关系错B、义齿固位差C、前牙咬切功能差D、下颌隆突处压痛E、说话及大开口的义齿脱落基托边缘需缓冲的是
在建筑材料的吸声种类中,( )主要吸中高频声。
城市燃气、热力管道工程施工过程中,在管道上开孔时,开孔不应开在焊缝上且开孔的边缘距焊缝之间的距离应大于()mm。
物流系统是由运输、仓储、包装、装卸搬运、配送、流通加工、物流信息等各环节所组成的,这些环节也称为物流的子系统。()
简述艾里克森人格发展理论。
统筹区域发展,促进区域协调发展,是我国经济社会发展的一个重点原则,坚持这一原则有利于()(2013年多选)
WhenthreeFloridaboyswerediagnosedashavingAIDS,theirbarberrefusedtocuttheirhairandtheirhousewasburneddownby
Whyisitsodifficulttofallasleepwhenyouareovertired?Thereisnooneanswerthat【C1】______toeveryindividual.Butman
最新回复
(
0
)