首页
登录
职称英语
[originaltext] [9]Not long ago it was assumed that the dangers man would mee
[originaltext] [9]Not long ago it was assumed that the dangers man would mee
游客
2024-04-07
26
管理
问题
[9]Not long ago it was assumed that the dangers man would meet in space would be terrible, the main ones being radiation and the danger of being hit by meteors. It is perhaps worth remembering that less than two’ centuries ago the dangers of train travel seemed similarly terrible. A man would certainly die, it was thought, if carried along at a speed of thirty kilometers per hour.
There are two sorts of radiation man must fear in space. [10]The first is radiation from the sun, and this is particularly dangerous when the sun is very active and explosions are occurring on its surface. The second, less harmful form comes from the so-called Van Allen Belts. These are two areas of radiation about 1,500 miles away from the earth. [11]Neither of these forms of radiation is a danger to us on the earth, since we are protected by our atmosphere. Specifically, it is that part of our atmosphere known as the ozonosphere which protects us. This is a belt of the chemical ozone between 12 and 21 miles from the ground, which absorbs all the radiation.
Once outside the atmosphere, however, man is no longer protected, and radiation can be harmful in a number of ways. A distinction must be drawn between the short- and long-term effects of radiation. The former are merely unpleasant, but just because an astronaut returning from a journey in space does not seem to have been greatly harmed, we cannot assume that he is safe. The long-term effects can be extremely serious, even leading to death.
9. What was one of the main dangers man would meet in space?
10. When is the sun radiation particularly dangerous to human beings?
11. Why did the speaker say neither of these forms of radiation is a danger to us?
选项
A、When the sun is very active and explosions occur.
B、When it is less than 1,500 miles away from the earth.
C、When bad weather occurs more frequently.
D、When there is less forest on the earth.
答案
A
解析
原文提及“太阳的辐射在太阳活跃时或在太阳表面有爆炸发生时尤其危险”。故A正确。
转载请注明原文地址:https://tihaiku.com/zcyy/3545414.html
相关试题推荐
[originaltext]Thegreatestimpetusforglobalizationtodayisnodoubtthe
[originaltext]AgrowingnumberofAmericanuniversitiesaredroppingtheen
[originaltext]AgrowingnumberofAmericanuniversitiesaredroppingtheen
[originaltext]Lasttimeweweretalkingabouttheneedforadvertising.Now
[originaltext]Lasttimeweweretalkingabouttheneedforadvertising.Now
[originaltext]Kuwaitisacountrywhichisquitesmall,butwhichisveryr
[originaltext]Kuwaitisacountrywhichisquitesmall,butwhichisveryr
[originaltext]Kuwaitisacountrywhichisquitesmall,butwhichisveryr
[originaltext]Mostdoctorshavelongbelievedthatreducingsaltcandecrea
[originaltext]Mostdoctorshavelongbelievedthatreducingsaltcandecrea
随机试题
NotfaroffthePacificcoastintheCostaRicanjungle,acommunityhastak
Acreditcardcanbeuseful.Youcouldtakeitintoastoreandbuyatelevi
3岁男性患者,因肺炎并发休克,24小时尿量350ml,血肌酐325μmol/L,
“万舞”是中国上古主要图腾舞蹈之一。()
某试验室拟设计一组质量比为石灰:粉煤灰:土=10:14:76的二灰稳定细粒土试件
全国社保基金境外投资限于下列投资( )。 ①银行存款 ②外国政府债券 ③
下列不属于晕针表现的是A:神志昏迷 B:血压升高 C:恶心欲吐 D:眩晕发
A.树干皮部渗出的油胶树脂 B.果实渗出的单树脂 C.树干渗出的香树脂 D
某甲作为投保人以其配偶某乙为被保险人向某保险公司投保了定期死亡保险,保险金额为2
A."知人爱人" B."医家十要" C."习医规格" D."医乃仁术"
最新回复
(
0
)