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
There are two main things that make aircraft engineering difficult: the need to make every component as reliable as possible and
There are two main things that make aircraft engineering difficult: the need to make every component as reliable as possible and
admin
2015-12-31
44
问题
There are two main things that make aircraft engineering difficult: the need to make every component as reliable as possible and the need to build everything as light as possible. The fact that an aeroplane is up in the air and cannot stop if anything goes wrong makes it perhaps a matter of life or death that its performance is absolutely dependable.
Given a certain power of engine, and consequently a certain fuel consumption, there is a practical limit to the total weight of aircraft that can be made to fly. Out of that weight as much as possible is wanted for fuel, radio navigational (航行的,航运的) instruments, passenger seats, or freight (货物) room, and, of course, the passengers or freight themselves. So the structure of the aircraft has to be as small and light as safety and efficiency will allow. The designer must calculate the normal load that each part will bear. This specialist is called the "stress man". He takes account of any unusual stress that may be put on the part as a precaution (预防, 预防措施) against errors in manufacture, accidental damage, etc.
The stress man’s calculations go to the designer of the part, and he must make it as strong as the stress man says is necessary. One or two samples are always tested to prove that they are as strong as the designer intended. Each separate part is tested, then a whole assembly—for example, a complete wing, and finally the whole aeroplane. When a new type of aeroplane is being made, normally only one of the first three made will be flown. Two will be destroyed on the ground in structural tests. The third one will be tested in the air.
The maximum possible weight of an aircraft is determined by______.
选项
A、international regulations
B、the number of passengers
C、the amount of freight room
D、the engine power
答案
D
解析
本题问飞机的最大的可能的重量是由什么决定的。文章第二段指出,在发动机指定的功率之下,油耗为某一定量,致使飞机能起飞,于是便有一个实际的临界重量,其中要尽可能多地计入燃料的重量、无线电导航仪、乘客座位或货舱的重量,当然,还要计入乘客及货物本身的重量。由此我们可以推断出本题的正确答案应是D“由发动机的功率决定的”。
转载请注明原文地址:https://kaotiyun.com/show/CmPO777K
0
在职攻硕英语联考
相关试题推荐
Globally,mostsmokersstartsmokingbeforetheageof18,withalmostaquarterofthosebeginningbeforetheageof10.Theyo
Americanshaveagreatloveforinformalityandnowhereisthisbetterexpressedthanintheirlovefornicknames(昵称、绰号).Upon
Isthecustomeralwaysright?Theanswer,itseems,dependsonwhichcountryyouarein.Shoppingisverymuchapartofacount
SpeakerA:DearJessica,whydon’tyoucomeonholidaywithus?SpeakerB:______
Heknewthathewouldbepunishedseverelybecauseofhisseriouserror.Thereforehe______awaythedaybeforeyesterday.
Whatoursocietysuffersfrommosttodayistheabsenceofconsensusaboutwhatitandlifeinitoughttobe.Suchconsensusca
Withitsanti-terrorismcampaigntaking______overanythingelse,thegovernmentisextendingitsjobandrunninginmoreaffairs
Intellectualpropertyrightsaretherightsgiventopersonsoverthecreationsoftheirminds.Theyusuallygivethecreatoran
Conventionalwisdomhasitthatconcernfortheenvironmentisaluxuryonlytherichworldcanafford;thatonlypeoplewhoseb
Artificialflowersareusedforscientificaswellasfordecorativepurposes.Theyaremadefrom【C1】______ofmaterials,suchas
随机试题
胼胝体干横断层面上的结构不包括
我国营养学会推荐,乳母每日膳食维生素A的摄入量为1200μg视黄醇当量,相当于()国际单位(IU)。
正注井的()压力,表示注入水自泵站,经过地面管线和配水间到注水井井口的压力。
设________.
患者男,23岁。因首次出现少语、少动、进食少半个月,加重3天入院。既往体健。患者在半个月前与女友分手后缓慢起病,讲话少,不主动与家人讲话,活动减少,基本不出门,有时见患者在自己房间里发呆,进食量比以前减少。近3天来,患者病情加重,不语不动不进食而被家人送入
露西是甲国公民,霍金是乙国公民,1995年露西和霍金在丙国结婚并生小孩凯西,甲、乙两国的国籍法规定两国采用的都是出生地主义,丙国采用血统主义,对于凯西的国籍,下列哪些地选项不正确?()
微分方程(3+2y)xdx+(1+x2)dy=0的通解为()。
关于监理机构人员结构,下列说法错误的是:()
诚实守信的基本要求不包括()。
一个类可以从直接或间接的祖先中继承所有属性和方法。采用这个方法提高了软件的【】。
最新回复
(
0
)