首页
登录
职称英语
A pilot cannot fly a plane by sight alone. In many conditions, such as flyin
A pilot cannot fly a plane by sight alone. In many conditions, such as flyin
游客
2025-02-02
10
管理
问题
A pilot cannot fly a plane by sight alone. In many conditions, such as flying at night and landing in dense fog, a pilot must use radar, an alternative way of navigating. Since human eyes are not very good at determining speeds of approaching objects, radar can show a pilot how fast nearby planes are moving. The basic principle of radar is exemplified by what happens when one shouts in a cave. The echo of the sounds against the walls helps a person determine the size of the cave. With radar, however, the waves are radio waves instead of sound waves. Radio waves travel at the speed of light, about 300, 000 kilometers in one second. A radar set sends out a short burst of radio waves: Then it receives the echoes produced when the waves bounce off objects. By determining the time it takes for the echoes to return to the radar set, a trained technician can determine the distance between the radar set and other objects. The word "radar," in fact, gets its name from the term "radio detection and ranging." "Ranging" is the term for detection of the distance between an object and the radar set. Besides being of critical importance to pilots, radar is essential for air traffic control, tracking ships at sea, and for tracking weather systems and storms. [br] Which of the following words best describes the tone of this passage?
选项
A、Argumentative.
B、Imaginative.
C、Explanatory.
D、Humorous.
答案
C
解析
推断题型通读全文可见本文使用举例的方式来讲解雷达的功用,工作原理,名字的来源等;因此可推断本文的语气是解释说明式的,选项C为答案。
转载请注明原文地址:https://tihaiku.com/zcyy/3939645.html
相关试题推荐
Apilotcannotflyaplanebysightalone.Inmanyconditions,suchasflyin
Apilotcannotflyaplanebysightalone.Inmanyconditions,suchasflyin
Apilotcannotflyaplanebysightalone.Inmanyconditions,suchasflyin
Apilotcannotflyaplanebysightalone.Inmanyconditions,suchasflyin
Apilotcannotflyaplanebysightalone.Inmanyconditions,suchasflyin
Thetwinsareso______thatIcannottellthemapart.A、alikeB、likelyC、likeD、li
Icannotthankyouverymuchforyourkindness,Iowemysuccesstoyou.A、soB、t
Thoughtheimitationjewelrycanfoolmanypeople,theycannot______uptoanexp
Hecannotseeanythingwithouthisglasses,sohemadea______ofrememberingto
Somemedicalconditionscanoftencurethemselves______,withoutmedicalinterve
随机试题
Skin.Itisthelargestorganofthebody.Skinisthebody’s【C1】______toin
Micro-EnterpriseCreditforStreetYouthA)Althoughsmall-sc
EatingDisordersA)Eatingdisordershavebeenmostc
OneinfiveUSworkersregularlyattendsafter-workdrinkswithco-workers,
假设某足球运动员的年薪为100万元,但若他从事其他职业,最多只能得到2万元,那么
没有围护结构、直径2.2m、高2m的屋顶圆形水箱,其建筑面积为()1112。
某公司正在启动一个新的系统集成项目,任命张某为项目负责人,并从多个职能部门抽调人
26岁,GP,孕41周,宫口开大4~5cm时,胎心听诊120次/分,胎心监测示"
油浸式电压互感器整体温升偏高,且中上部温度高,温差为(),可判断为内部绝
某公司2012年提取公积金后的税后净利润为8000万元,2013年投资计划所需资
最新回复
(
0
)