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
【C1】______ nearly a hundred years of powered flight, scientists are still trying to figure out how birds fly. Researchers have
【C1】______ nearly a hundred years of powered flight, scientists are still trying to figure out how birds fly. Researchers have
admin
2010-01-10
78
问题
【C1】______ nearly a hundred years of powered flight, scientists are still trying to figure out how birds fly.
Researchers have learned that the slapping noise pigeons make when they suddenly take off is the sound of super charged lift. They call it the "clap fling" effect.
Here at SRI International scientists try to duplicate the pigeons’ thrust. A flashing strobe reveals the secret.
Scott Stanford, a scientist at SRI, says, You re looking at the clap fling effect, where the two wings will come together and peel apart 【C2】______ each other, thus augmenting lift 【C3】______ drawing air from the top to the bottom. "
This mechanical bug won’t get off the ground. 【C4】______ its flapping wings demonstrate a potential propulsion system for robotic birds: man-made rubbery muscle.
Roy Kornbluh works at SRI. "There, I’m turning the voltage on and off, and you can see when the voltage is on, the material is larger 【C5】______ when the voltage is off."
Super computers show high-speed airflows over supersonic aircraft.
But scientists have only begun to see how air flows 【C6】______ really low speeds.
Professor Max Platzer of the Naval Postgraduate School, says, "The flapping wing is generating a thrust, this way, this is the basic physics of the phenomenon."
It’s pelicans--not pigeons--the Navy is looking at. The Navy is looking at the smooth easy flight of pelicans low over water--called "ground effect." Researchers at the Naval Postgraduate School are trying to imitate the pelican’s efficiency.
Assistant Professor Kevin Jones of the Naval Postgraduate School says, " 【C7】______ flapping the wings, symmetrically, we’re 【C8】______ effect imitating ground effect. We now have the same feature a bird sees when it’s flying, over a ground plane."
An electric motor drives the flapping wings. Researchers here are working 【C9】______ ways to beam power to the tiny bird.
David Jenn of the Naval Postgraduate School says, "There’s no battery inside of here, so we’re going to set this inside the radar beam, and the energy is extracted from the radar beam and will be used to propel the motor."
Scientists are learning it’s one thing to build an airplane, 【C10】______ quite another to build a bird.
【C4】______
选项
答案
but
解析
转载请注明原文地址:https://kaotiyun.com/show/vDKd777K
本试题收录于:
BEC高级阅读题库BEC商务英语分类
0
BEC高级阅读
BEC商务英语
相关试题推荐
A、 B、 C、 D、 BTheequipment,theuniforms,andtheenvironmentsuggestscientistsinalaboratory.Choice
Whatisthewoman’sproblem?
Whatisthereasonfortheflightdelay?
A、 B、 C、 C当问句是以when开头的时候,要用表示时间的词进行回答。(A)用来回答以why开头的问句。(B)是利用application的动词形式apply设下的陷阱。所以正确答案是(C)。
CanyoutelluswhyyoudecidedtolearnEnglish?(Couldyoutelluswhichforeignlanguagesyouthinkwillbemostimportantin
Istimemanagementimportantornot?Why?
CooperationforaNewBusinessYourcompanyisinternationalandveryfamousforchocolates.TheCEOofanotherfamouscompanyw
•Youwillhearabusinesspresentationabout3simplesellingtactics.•Asyoulisten,forquestions1—12,completethenotes,
•Youwillhearabusinesspresentationabout3simplesellingtactics.•Asyoulisten,forquestions1—12,completethenotes,
•Youwillhearabusinesspresentationabout3simplesellingtactics.•Asyoulisten,forquestions1—12,completethenotes,
随机试题
促胃液素瘤引起的腹泻属于()
某建设工程施工过程中,施工单位甲与材料供应商乙约定了材料采购合同,约定于次年1月22日交货,到了约定时间乙并未按照约定交付材料给甲造成了损失,甲方没有采取任何措施减损,导致损失扩大到6万元。甲以乙违约为由向乙主张赔偿,甲方与乙方就此违约事实发生纠纷,经过鉴
在建设工程项目决策阶段,建设单位职业健康安全与环境管理的任务包括()。
弗里德曼认为,人们的货币需求稳定,货币政策应实行( )。
自由竞争的资本主义在()发展到鼎盛时期。
河南省的()是中国第一座官办寺院。
设曲面方程为x2+y2+z2-2x+2y-4z-3=0,求过点(3,-2,4)的切平面方程。
【案例一】每天早晨晨间活动结束的时候,我就会拿起点名册,准备点名。这天,我对孩子们说:“今天老师不用嘴巴来点名,而是用眼睛来点名。”他们一脸的疑惑,好像在问,眼睛怎么可以用来点名呢?眼睛又不能说话。我看着他们说:“我用眼睛看着你,对你眯眯笑,就是在点你的名
智商很低的人肯定不能成名成家,但智商很高的人不一定能成名成家。在导致人成名成家的其他因素中,大部分属于情商。由此可以推出()
面向对象程序设计有许多特性,下列不是面向对象程序设计特性的是()。
最新回复
(
0
)