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
32
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.
【C3】______
选项
答案
by
解析
转载请注明原文地址:https://kaotiyun.com/show/qDKd777K
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
Howlonghastheflightbeendelayed?
A、 B、 C、 CAboutthreehundredpagesanswershowmany.Choice(A)confusesthesimilarsoundsageandpage.Choice(
Whattypeofbusinessisbeingadvertised?
Whatkindofbusinessisbeingadvertised?
A、 B、 C、 A问是否需要经营学学位的Do动词一般疑问句。(B)是对问时间长度的HowIong疑问句可能的回答:(C)是使用由position可能联想到的HumanResources、含联想词错误的错误选项。因此
Communication:thefactorsinvolvedingivinganeffectivepresentation
Isadvertisingimportantornot?Whatfactorsmustonetakeintoaccountwhendevelopingadvertisingstrategy?
CooperationforaNewBusinessYourcompanyisinternationalandveryfamousforchocolates.TheCEOofanotherfamouscompanyw
•Youwillhearabusinesspresentationabout3simplesellingtactics.•Asyoulisten,forquestions1—12,completethenotes,
•Youwillhearabusinesspresentationabout3simplesellingtactics.•Asyoulisten,forquestions1—-12,completethenotes,
随机试题
畸形工件的基准选择一般情况下是()。
【背景资料】A、B两座相同的仓库项目,总建筑面积7000m2。施工时分A、B分区,项目经理下分设两名栋号经理,每人负责一个分区,每个分区又安排了一名专职安全员。项目经理认为,由栋号经理负责每个栋号的安全生产,自己可以不管理安全事项。A区
下列不是产生淹塔的原因是()。
一些心理学家声称,人们出门在外时可能会感到孤独。
临床上最常见的输血反应是
应置于干燥阴凉处或2~10℃冷藏保存的药物是()
教育改革的核心是【】
六声调式并不能作为一种单独的调式,它只是在五声音阶中增加一个偏音,或是在七声音阶中减少________而形成的一种临时的调式。
上海市人民政府发布的《上海市城镇职工基本医疗保险办法》属于()。
2014年1~11月我国货物运输情况2013年1~10月我国货物运输总量最大的领域是:
最新回复
(
0
)