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
自考
The basic principle of radar is illustrated by what happens when one shouts in a cave. The echo of the shouting (11)______ the
The basic principle of radar is illustrated by what happens when one shouts in a cave. The echo of the shouting (11)______ the
admin
2009-01-10
83
问题
The basic principle of radar is illustrated by what happens when one shouts in a cave. The echo of the shouting (11)______ the walls helps a person determine the size of the cave. With radar,however,the waves are radio waves instead of (12)______ waves. Radio waves travel (13)______ the speed of light,about300,000 kilometers in a second. A radar set (14)______ a short burst of radio waves. Then it receives the echoes (15)______ when the waves bounce(反射) off objects. By determining the time it (16)______ for the echoes to return to the radar set,a trained technician (17)______ determine the distance between the radar set and other objects. The word“radar”, (18)______ ,gets its name from the term“radio detection and ranging. ”“Ranging”is the term for detection of the (19)______ between an object and the radar set.
Besides being of critical importance to pilot,radar is (20)______ for air traffic control,for tracking ships at sea,and for tracking weather systems and storms.
选项
A、length
B、width
C、distance
D、space
答案
C
解析
该句为物体与雷达之间的距离。故选C。
转载请注明原文地址:https://kaotiyun.com/show/29AR777K
本试题收录于:
英语(二)题库公共课分类
0
英语(二)
公共课
相关试题推荐
标志着新民主主义革命理论成为科学理论体系的论著是【】
科学发展观的第一要义是()
日常的,例行的a.r______
RobReiner,co-founderofCastleRockEntertainment,wasgreadtlysurprisedwhenhesawhisstudio’sfilmProofofLife.“Wow,why
cuttendencychangesgrowthdifficultiesdegreegraduationworryingfailedresultriserepor
______nofrictionbetweenthesurfaceoftheroadandourfeet,wecouldnotwalkatall.
Manyawriterofnewspaperarticles______(have)turnedtowritingnovels.
Henry’sjobwastoexaminecarswhichcrossedthefrontiertomakesurethattheywerenotsmugglinganythingintothecountry.
A.seriousandprofessionalB.theyweremembersofdifferentorganizationsC.hospitaldoctorsstopwearingtiesD.whodoesno
TheMind-BodyConnectionsNormanCousinswasafamousAmericanmagazineeditor.In1964,hereturnedfromanoverseastripa
随机试题
2011年8月7日,家住东区的甲向西区法院起诉乙,要求法院判决乙交付合同项下的三辆卡车。法院于9月15日作出一审判决,判决乙在判决生效后1个月内向甲交付价值30万元的A、B、C三辆卡车,并承担全部诉讼费用。乙缴纳了诉讼费用,但并没有将小轿车交给甲。上诉期满
诊断子宫绒毛膜细胞癌最可靠的依据是()。
下列()属于促进长期增长的政策。
财政管理体制的内容主要有()。
要带团到新的旅游景点或不熟悉的景点参观浏览,导游员应事先了解其概况,如()。
一般资料:求助者,男性,28岁,医院主治医师。案例介绍:求助者在大学时与同学谈恋爱,计划毕业后结婚。但毕业后女友出国留学,结婚的事就耽误了下来。四年来女友不断催促他出国,可他放不下自己在国内某著名医院的工作和发展机会,反而力劝女友回国发展,遂与女
首长制和委员会制是依据行政组织拥有最终的决策权承担责任人数的多少来划分的。()
Therewasonethoughtthatairpollutionaffectedonlytheareaimmediatelyaroundlargecitieswithfactoriesandheavyautomob
ThebestbirthdayI’veeverhadwasmy21st.Myfamilytoldmetheyweregoingto【C1】______meouttodinner,butinfacttheypl
Accordingtothewriter,whatisagoodbook?
最新回复
(
0
)