首页
登录
职称英语
The marvelous telephone and television network that has now enmeshed the who
The marvelous telephone and television network that has now enmeshed the who
游客
2025-04-06
5
管理
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. [br] The author of the passage, readers can infer, intends to show the______.
选项
A、limitations of our technology
B、vastness of the cosmic reality
C、prospect of planetary travel
D、psychological impact of time and space
答案
C
解析
读者可以推断,本文作者想要说明到行星上旅行的前景。从第六段的结尾和整个第七段可以看出,作者的态度是乐观的,他无疑是在展望到行星上去旅行的前景。
转载请注明原文地址:https://www.tihaiku.com/zcyy/4028834.html
相关试题推荐
Themarveloustelephoneandtelevisionnetworkthathasnowenmeshedthewho
Themarveloustelephoneandtelevisionnetworkthathasnowenmeshedthewho
Themarveloustelephoneandtelevisionnetworkthathasnowenmeshedthewho
Despitetheweb,wewatchmoretelevisionthanever.Inthechaosoftod
Despitetheweb,wewatchmoretelevisionthanever.Inthechaosoftod
Despitetheweb,wewatchmoretelevisionthanever.Inthechaosoftod
Despitetheweb,wewatchmoretelevisionthanever.Inthechaosoftod
Fromthehealthpointofviewwearelivinginamarvelousage.Weareimmun
Fromthehealthpointofviewwearelivinginamarvelousage.Weareimmun
Comparisonsweredrawnbetweenthedevelopmentoftelevisioninthe20thcen
随机试题
WhenDonaldarrivedforhisfirstgroup-therapysessionhewasinawheelcha
Wedon’tallow______inthemeetingroom.A、tosmokeB、smokedC、smokingD、tosmoki
Lazinessisasin,everyoneknowsthat.Wehaveprobablyallhadlecturespo
合同的平等主体(即当事人)包括()。A.法人 B.自然人 C.其他组织
下列哪个是安装在物料提升机吊笼上沿导轨运行,可防止吊笼运行中偏移或摆动,保证吊笼
患者,男,32岁,3天前淋雨,次日出现寒战、高热,继之咳嗽,咳少量脓性痰,伴右侧
治头痛,无论风寒、风热、风湿、血虚、血瘀皆可选用的药为A、川芎 B、延胡索
王某、于某、李某和赵某共同开办了一家房地产经纪公司B公司,王某和于某是房地产经纪
浇筑混凝土必须间歇时,间歇最长时间与()有关。A、水泥品种B、混凝土初凝时间
建设单位在地下管线工程竣工验收前,应当提请()对地下.管线工程档案进行专项预验
最新回复
(
0
)