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
The marvelous telephone and television network that has now enmeshed the whole world, making all men neighbors, cannot be extend
The marvelous telephone and television network that has now enmeshed the whole world, making all men neighbors, cannot be extend
admin
2013-01-20
57
问题
The marvelous telephone and television network that has now enmeshed the whole world, making all men neighbors, cannot be extended into space. It will never be possible to converse with anyone on another planet. Even with today’s radio equipment, the messages will take minutes——sometimes hours——on their journey, because, radio and light waves travel at the same limited speed of 186, 000 miles a second.
Twenty years from now you will be able to listen to a friend on Mars, but the words you hear will have left his mouth at least three minutes earlier, and your reply will take a corresponding time to reach him. In such circumstances, an exchange of verbal messages is possible-but not a conversation.
To a culture which has come to take instantaneous communication for granted, as part of the very structure of civilized life, this "time barrier" may have a profound psychological impact. It will be a perpetual reminder of universal laws and limitations against which not all our technology can ever prevail. For it seems as certain as anything can be that no signal——still less any material object——can ever travel faster than light.
The velocity of light is the ultimate speed limit, being part of the very structure of space and time. Within the narrow confines of the solar system, it will not handicap us too severely. At the worst, these will amount to twenty hours——the time it takes a radio signal to span the orbit of Pluto, the outer most planet.
It is when we move out beyond the confines of the solar system that we come face to face with an altogether new group of cosmic reality. Even today, many otherwise educated men- like those savages who can count to three but lump together all numbers beyond four-cannot grasp the profound distinction between solar and stellar space. The first is the space enclosing our neighbor-ring worlds, the planets; the second is that which embraces those distant suns, the stars, and it is literally millions of times greater. There is not such abrupt change of scale in the terrestrial affairs.
Many conservative scientists, shocked by these cosmic gulfs, have denied that they can ever be crossed. Some people never learn; those who sixty years ago laughed at the possibility of flight, and ten years ago laughed at the idea of travel to the planets, are now quite sure that the stars will always be beyond our reach. And again they are wrong, for they have failed to grasp the great lesson of our age—— that if something is possible in theory, and no fundamental scientific laws oppose its realization, then sooner or later it will be achieved.
One day we shall discover a really efficient means of propelling our space vehicles. Every technical device is always developed to its limit and the ultimate speed for spaceships is the velocity of light. They will never reach that goal, but they will get very near it. And then the nearest star will be less than five years of voyaging from the earth.
Confronted with the new groups of cosmic reality, many educated men ______.
选项
A、become ignorant savages again
B、find the "time barrier" unbearable
C、will not combine solar and stellar space
D、cannot adapt to the abrupt change of scale
答案
D
解析
第五段中说到许多受过教育的人不能抓住太阳系与其他星系之间的深刻不同。……在地球上没有如此突然的大规模的改变。所以D是正确答案。
转载请注明原文地址:https://kaotiyun.com/show/6v2O777K
0
考博英语
相关试题推荐
Youcan’tbe______carefulinmakingthedecisionasitwassuchacriticalcase.
Therearethreeseparatesourcesofhazard【1】totheuseofnuclearreactiontosupplyuswithenergy.Firstly,theradioactivem
Thedifferencebetweenaliquidandagasisobvious【l】theconditionsoftemperatureandpressurecommonlyfoundatthesurface
Theboardofthecompanyhasdecidedto______itsoperationtoincludeallaspectsoftheclothingbusiness.
Itisour_____policythatwewillachieveunitythroughpeacefulmeans.
Sometimesartistsfindithardfortheirworkstowinpopular_____.
Unilever,oneoftheworld’slargestconsumerproductscompanies,aimstoadd______tolifebymeetingeverydayneedsfornutrit
Itisrequiredthatduringtheprocessgreatcarehastobetakentoprotectthe______silkfromdamage.
Practicallyspeaking,theartistematuringofthecinemawasthesingle-handedachievementofDavidW.Griffith(1875~1948).Bef
随机试题
男孩,7岁,浮肿4d,气促1d,伴尿少,尿色深。查体:R32/min,心音增强,两肺底部有少许湿性啰音,肝肋下2cm,BP20/12kPa(150/90mmHg),首先考虑诊断是
男,72岁,糖尿病史15年,长期口服二甲双胍,空腹血糖维持在7~9mmol/L。尿白蛋白排泄率为240mg/24h。LDL—胆固醇5.08mmol/L。查体:BP160/95mmHg,心肺未见明显异常,双下肢轻度可凹性水肿。有关该患者的治疗,错误的是
下列法律事实中属于法律事件的是:()。
岩土工程勘察中采用75mm单层岩芯管和金刚石钻头对岩层钻进,其中某一回次进尺1.00m,取得岩芯7块,长度分别依次为6cm、12cm、10cm、10cm、10cm、13cm、4cm,评价该回次岩层质量的正确选项是哪一个?
【背景资料】某建筑空调工程中的冷热源主要设备由某施工单位吊装就位,设备需吊装到地下一层(-7.500),再牵引至冷冻机房和锅炉房就位。施工单位依据吊装设备一览表(见下表)及施工现场条件(混凝土地坪)等技术参数进行分析、比较,制订了设备吊装施工方案
公民赵某在某纳税年度10月取得如下收入:(1)工资收入1500元;(2)利用业余时间进行演讲取得收入28000元;(3)取得特许权使用费3000元,拿出1000元通过民政局捐赠养老院;(4)出版一部长篇小说,取得稿酬40000元;
甲企业为增值税一般纳税人,适用的增值税税率为17%,因保管车辆的需要,2017年1月该企业决定采用自营方式建造一栋车库。相关资料如下:(1)2017年1月至6月,购入车库工程物资100万元,增值税17万元;发生运输费用5万元,增值税0.55万元;全部
美国首先提出建立国际联盟,后来却没有参加,其根本原因在于()。
简述保险诈骗罪的表现形式。
Hewalkeddownthehills,______(sing)softlytohimself.
最新回复
(
0
)