首页
登录
职称英语
Bird wings have a much more complex job to do than the wings of an airplane,
Bird wings have a much more complex job to do than the wings of an airplane,
游客
2025-04-12
24
管理
问题
Bird wings have a much more complex job to do than the wings of an airplane, for in addition to supporting the bird they must act as its engine, rowing it through the air. Even so the wing outline or a bird conforms to the same aerodynamic principles as those eventually discovered by people when designing airplanes, and if you know how different kinds of aircraft perform, you can predict the flight capabilities of similarly shaped birds.
Short, stubby wings enable a tanager and other forest-living to swerve and dodge at speed through the undergrowth, just as they helped the fighter planes of the Second World War to make tight turns and acrobatic maneuvers in a dog-fight. More modern fighters achieve greater speeds by sweeping back their wings while in flight, just as peregrines do when they go into a 130kph dive, swooping to a kill. Championship gliders have long, thin wings so that, having gained height in a thermal up-current they can soar gently down for hours and an albatross, the largest of flying birds, with a similar wing shape and a span of 3 meters, can patrol the ocean for hours in the same way without a single wing beat. Vultures and hawks circle at very slow speeds supported by a thermal and they have the broad rectangular wings that very slow-flying aircraft have. People have not been able to adapt wings to provide hovering flight. That has only been achieved with the whirling, horizontal blades of a helicopter or the downward-pointing engines of a vertical landing jet. Hummingbirds have paralleled even this. They tilt their bodies so that they are almost upright and then beat their wings as fast as 80 times a second producing a similar downdraft of air. So the hummingbird can hover and even fly backwards. [br] Which of the following is NOT true according to the passage?
选项
A、Bird wings have to support the bird.
B、Bird wings must act as the bird’s engine.
C、Airplane’s wings must act as the airplane’s engine.
D、Similar wing shapes in aircraft and birds produce similar flight capabilities.
答案
C
解析
题目问:根据文章内容,哪项不是真实的?第一段“Bird wings have a much more complex job todo than the wings of an airplane,for in addition to supporting the bird they must act as its engine,rowing it through the air.”通过这句话可知,与飞机的机翼相比,鸟的翅膀的功能更复杂,它能支持鸟体,还是鸟飞翔的引擎。据此判断,应选择C。
转载请注明原文地址:https://tihaiku.com/zcyy/4034469.html
相关试题推荐
Birdwingshaveamuchmorecomplexjobtodothanwingsofanairplane,for
Birdwingshaveamuchmorecomplexjobtodothanwingsofanairplane,for
Birdwingshaveamuchmorecomplexjobtodothanthewingsofanairplane,
Birdwingshaveamuchmorecomplexjobtodothanthewingsofanairplane,
Insuchachanging,complexsocietyformerlysimplesolutionstoinformation
Insuchachanging,complexsocietyformerlysimplesolutionstoinformation
Insuchachanging,complexsocietyformerlysimplesolutionstoinformation
Insuchachanging,complexsocietyformerlysimplesolutionstoinformation
Insuchachanging,complexsocietyformerlysimplesolutionstoinformation
Insuchachanging,complexsocietyformerlysimplesolutionstoinformation
随机试题
WhichofthefollowingpoemsisNOTwrittenbyAlfredTennyson.A、PoemsbyTwoBr
It’sthedreamofmanyanofficedweller:Retireextremelyearlyandtravel
Mr.Nathan,LadiesandGentlemen:TomorrowMr.Nathanwillconcludehisvisit
Accordingtothepassage,whendidHerakleionandEasternCanopusdisappear?[br
百日咳(咳嗽的临床表现与分型)()A:咳嗽伴有鸡鸣样吸气回声,病程长达2~3个月
儿童在游戏中主要表现在以物代物、以人代人、以假想的情景和行动方式将现实生活和自己
具有阻断多巴胺D2受体活性和抑制乙酰胆碱酯酶活性,且无致心律失常不良反应的促胃肠
某公司2018年实现的净利润为500万元,2018年年初未分配利润为200万元,
当软土地层平坦,横坡缓于1:10时,抛石挤淤法处理软基中,抛投顺序正确的是(
工程建设定额按编制程序和用途可分为( )。A.施工定额 B.预算定额 C.概
最新回复
(
0
)