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
Why were the Wright brothers able to succeed in an effort at which so many others had failed? Many explanations have been mentio
Why were the Wright brothers able to succeed in an effort at which so many others had failed? Many explanations have been mentio
admin
2011-02-28
32
问题
Why were the Wright brothers able to succeed in an effort at which so many others had failed? Many explanations have been mentioned, but three reasons are most often cited. First, they were a team. Both men worked congenially and cooperatively, talked incessantly about the possibility of manned flight, and served as a conscious source of inspiration and encouragement to each other.
Both were glider pilots. Unlike some other engineers who experimented with the theories of flight, they experienced the practical aspects of aerodynamics by building and flying in kites and gliders. They had realized from their experiments that the most serious challenge in manned flight would be stabilizing and maneuvering the aircraft once it was airborne. While others concentrated their efforts on the problem of achieving lift for take-off, they were focusing on developing a three- axis control for guiding their aircraft.
In addition, the Wright brothers had designed more effective wings for the airplane than had been previously engineered. Using a wind tunnel, they tested more than two hundred different wing designs, recording the effects of slight variations in shape on the pressure of air on the wings. The data from these experiments allowed the Wright brothers to construct a superior’ wing for their aircraft.
In spite of these advantages, however, the Wright brothers might not have succeeded had they not been born at precisely the opportune moment in history. Attempts to achieve manned flight in the early nineteenth century were doomed because the steam engines that powered the aircrafts were so heavy in proportion to the power that they produced. But by the end of the nineteenth century, when the brothers were experimenting with engineering options, a relatively light internal combustion engine had already been invented, and they were able to bring the ratio of weight to power within acceptable limits for flight.
Why does the author suggest that the experiments with the wind tunnel were important?
选项
A、Because they allowed the Wright brothers to decrease the weight of their airplane.
B、Because they resulted in a three-axis control for their airplane.
C、Because they were important in the refinement of the wings for their airplane.
D、Because they used the data to improve the engine for their airplane.
答案
C
解析
从文章第三段可以推断,目的在于找出最佳的机翼形状。
转载请注明原文地址:https://kaotiyun.com/show/6Wtd777K
本试题收录于:
公共英语三级笔试题库公共英语(PETS)分类
0
公共英语三级笔试
公共英语(PETS)
相关试题推荐
Schoolsofeducationhavelongbeenobjectsofcriticism.FromJamesKoorner’s1963book,TheMiseducationofAmerica’sTeachers
Schoolsofeducationhavelongbeenobjectsofcriticism.FromJamesKoorner’s1963book,TheMiseducationofAmerica’sTeachers
Schoolsofeducationhavelongbeenobjectsofcriticism.FromJamesKoerner’s1963book,TheMiseducationofAmerica’sTeachers
Schoolsofeducationhavelongbeenobjectsofcriticism.FromJamesKoerner’s1963book,TheMiseducationofAmerica’sTeachers
Parentsnowhaveapopularbeliefthatschoolsarenolongerinterestedinspelling.NoschoolIhavetaughtinhaseverignored
WhichofthefollowingisNOTmentionedinthepassage?
Thispassageismainlyconcernedwith______.WhichofthefollowingisNOTmentionedinthepassage?
WhichofthefollowingfactorisNOTmentionedwhendiscussingthepersonsinterviewedintheresearch?Whatisthebesttitle
随机试题
国际旅游组织
A.0期去极速度快、幅度高B.4期自动去极C.两者都是D.两者都不是浦肯野细胞动作电位的特征是
为减轻不适感,子宫脱垂病人用1:5000高锰酸钾溶液坐浴,正确的是( )。
下列关于滴虫性阴道炎病人的健康指导不正确的是
碾压混凝土坝是采用碾压土石坝的施工方法,使用干贫混凝土修建的混凝土坝,是混凝土坝施工的一种新技术。某拦河大坝采用该项施工技术。承包商在编制施工组织设计时,根据有关资料,结合现场地形地貌等条件,重点对下列几个方面进行分析和考虑:(1)料场的选择与布置;(
旅游车被一卡车从后撞击,造成数名游客轻伤,一名游客骨折,对此导游人员应采取的正确措施有()。
导游人员应具备的旅行常识有()等。
清正廉明,其要点是:艰苦奋斗,(),防腐拒贿,()。
密码只由数字1、2、3、4、5组成,这些数字由左至右写成且符合下列条件才能组成密码。这组数字满足以下条件:①密码最短为两个数字,可以重复;②1不能为首;③如果在某一密码文字中有2,则2就得出现两次以上;④3不可为最后一个字母,也不可为倒数第二个字母
胡适认为,英雄人物“一言可以兴邦,一言可以丧邦”。这种观点是
最新回复
(
0
)