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
专升本
A very interesting and important development in science is a device called laser. A laser is a machine which produces a light be
A very interesting and important development in science is a device called laser. A laser is a machine which produces a light be
admin
2019-03-28
42
问题
A very interesting and important development in science is a device called laser. A laser is a machine which produces a light beam. The light produced by a laser is a very special kind of light. The light, called a laser beam, is powerful and can be made to do many things. The laser was first developed in 1960, about more than half a century ago.
There are many different uses for lasers and several different types have been developed. Some use gases to produce the light beam. The gases are heated and cooled, and these processes cause the gases to produce energy in the form of light. One special point of lasers is that the light beam can be stored. If the stored light is then suddenly let go, it is extremely powerful. The light from a laser beam can be used either by storing it and letting it go suddenly, or by using it in a continuous stream.
There are three important areas where the control of the laser beam has been put into use by scientists. These areas are industry, communications, and medicine. In each area, the scientists have been able to use the laser to do things that they could not do in another way. The laser has been very helpful.
In industry, the laser beam has been used for measurement and drilling. When something large is being built—for example, a large bridge—it is important to have very accurate measurements. By accurate measurement, lasers are also helpful in laying down pipelines over long distances. As lasers become more common in industry, there will be more and more uses for them.
What is important in building large things?
选项
A、To drill holes accurately.
B、To lay down long pipelines.
C、To cut pipes by lasers.
D、To measure accurately.
答案
D
解析
根据最后一段第二句“When something large is being built—for example,a large bridge—it is important to have very accurate measurements.”可知,在建造大型建筑物时,精确的测量很重要。故选D。
转载请注明原文地址:https://kaotiyun.com/show/NBJC777K
本试题收录于:
英语题库普高专升本分类
0
英语
普高专升本
相关试题推荐
A:Allfight.It’stheonlywayI’llbeabletolearnEnglishfastenough,Iguess.
Packagingisanimportantformofadvertising.Apackagecansometimesmotivatesomeonetobuyaproduct.Forexample,asmallc
Thehumanbraincontains10thousandmillioncellsandeachofthesemayhaveathousandconnections.Suchenormousnumbersused
Dr.RichardStevens,aSeniorLecturerinPsychologyattheOpenUniversity,giveshisopiniononcloning:"Cloningisaver
ItwasnotuntilinmylatethirtiesthatImadethisimportantdiscovery:giving-awaymakeslifesomuchmoreexciting.
Afriendofminemetwithanaccidentdrivingindarkness.Hislegsweresohurtthathecouldn’tmove.Whatwasthe【C1】______w
______fortheirsupport,hewouldhavegonepenniless.
Everyoneisexposedtoit,sonaturallysomepeoplewillimitatewhattheyseeonTV,whattheyreadinthenewspapersandwhat
Inmostcultures,whenyoumeetacquaintancesforthefirsttimeduringaday,itisnormaltogreetthem.Themainpurposeoft
Enoughsleepisimportanttohealth.Theamountofsleep【C1】______dependsontheageofthepersonandtheconditionsinwhichs
随机试题
俄罗斯联邦安全会议是________________________机构,也是保障俄罗斯国家安全的最高决策机构。
椎动脉型颈椎病主要症状表现为
在进行多普勒检查时,无须特别关注的是
枕左前位胎头进入骨盆入口时衔接的径线是
诊断神经性厌食时,BMI不高于
芦荟功能芒硝功能
齐云山是一座道教名山,与()齐名。
不在豫菜十大传统名菜的是()
根据下面表格资料,回答第136~140题。请根据下表中所示,回答以下问题:某省规定,公务员考试分笔试和面试两个程序。笔试合格后才有资格进入面试,只有两种考试皆合格才能录取。本次公务员考试的最终录取率为()
We’dratheryou______theaccounttomorrow.
最新回复
(
0
)