首页
登录
职称英语
As in the field of space travel, so in undersea exploration new technologies
As in the field of space travel, so in undersea exploration new technologies
游客
2023-12-09
34
管理
问题
As in the field of space travel, so in undersea exploration new technologies continue to appear. They share a number of similarities with each other--as well as some important differences.
Manned submersibles, like spaceships, must maintain living conditions in an unnatural environment. But while a spaceship must simply be sealed against the vacuum of space, a submersible must be able to bear extreme pressure if it is not to break up in the deep water.
In exploring space, unmanned vehicles were employed before astronauts. In undersea exploration, on the other hand, men paved the way, and only recently have unmanned re- mote-operated vehicles (ROVs) been put to use.
One reason for this is that communicating with vehicles in orbit is much easier than talking to those underwater. A vacuum is an ideal medium for radio communications, but underwater communications are limited to much slower sound waves. Thus, most undersea vehicles-particularly ROVs-operate at the end of long ropes.
For a similar reason, knowing where you are undersea is much more difficult than in space. A spaceship’s position can be located by following its radio signal, or by using telescopes and radar. For an undersea vehicle, however, a special network of sonar devices must be laid out in advance on the ocean floor in the area of a dive to locate the vehicle’s position.
Though undersea exploration is more challenging than outer space in a number of aspects, it has a distinct advantage, going to the ocean depths doesn’t require the power necessary to escape Earth’s gravity. Thus, it remains far less expensive. [br] Which of the following is NOT mentioned in the passage?
选项
A、New techniques are continually developed and new machines invented for undersea exploration.
B、If not well built, a submersible is most likely to get crushed in deep water.
C、A submersible, when manned, looks very like a spaceship.
D、In certain respects undersea exploration is often faced with the same problem as the space exploration.
答案
C
解析
“New techniques are continually developed and new machines invented for undersea exploration”,这在第一和第三段中提及过;“If not well built, a submersible is most likely to get crushed in deep water”,这在第二段最后一句话中提到过;“In certain respects undersea exploration is often faced with the same problem as the space exploration”,在第一段末提到过。尽管文章第二段提及“Manned submersibles, like spaceships, must maintain living conditions in an unnatural environment”,但不能将其理解为“A submersible, when manned, looks very like a spaceship”,可见选择项[C]在文中没有被提及,所以是正确答案。
转载请注明原文地址:https://tihaiku.com/zcyy/3257981.html
相关试题推荐
OnJuly7th,IwastravelinginLondon.Iwashavingbreakfastatahotelve
OnJuly7th,IwastravelinginLondon.Iwashavingbreakfastatahotelve
AnairlinertravellingfromLondontoNewYorkmaytakefromfivetofifteen
AnairlinertravellingfromLondontoNewYorkmaytakefromfivetofifteen
WhichisthemasterpiecebyJonathanSwift?A、RobinsonCrusoeB、Gulliver’sTravel
TravellingintheJungleTherearealotofdifficultiest
TravellingintheJungleTherearealotofdifficultiest
TravellingintheJungleTherearealotofdifficultiest
TravellingintheJungleTherearealotofdifficultiest
TravellingintheJungleTherearealotofdifficultiest
随机试题
Everybodywastestime.Insteadofdoinghishomework,theschoolboywatches
BeforehefoundedOculusVR,PalmerLuckeyworkedattheUniversityofSouth
[img]2012q2/ct_etoefm_etoeflistz_0720_20124[/img]Inthispartofthesectio
%hebasicfeaturesofthecommunicationprocessareidentifiedinonequestion:
Alandfreefromdestruction,pluswealth,naturalresources,andlaborsupp
男性病人,38岁,4小时前负重物时,右侧腹股沟斜疝嵌顿,下列表明疝内容物已发生缺
沉降观测位置发生位移应如何检修?()(A)及时清理杂物(B)必要时对观测
下列关于2009年各省市校均招生人数的描述,正确的是 A、广东多于山西
影响期权价格的因素包括标的资产的价格、流动率、红利收益、存储成本及合约期限。(
(2015年真题)关于证人证言与鉴定意见,下列哪一选项是正确的?A.证人证言只能
最新回复
(
0
)