ATrainFloatingOnAirAtrainthatfloatsonair?It'snotmagic―i...
问题详情:
A Train Floating On Air
A train that floats on air? It's not magic― it's magnets. And it's close to reality.
In Virginia USA the fall of 2002, a train with no wheels traveled on air and carried college students across their campus. In Japan, a whisper-quiet railway engine hovered and raced at 350 miles per hour using magnets and electricity as the power. And in China, a magnet train line linked Shanghai with nearby Pudong Airport.
These trains use magnetic levitation technology, “maglev” for short. They use the same rules as the magnets you pick up at home or school: opposite poles of magnets attract each other, and like poles repel each other.
How does it work?
Powerful magnets on the bottom of the train repel magnets on the track, which is actually just a magnet-filled guiding way. With a magnetic field of sufficient force, the train will go hovering on air, which seemed impossible to us in the past.
When an electrical current is sent through the track, the train moves. Turn the current backwards and the train slows down.
Maglev doesn't rely on the friction of wheels on track, so it can climb a much steeper hill than a traditional train. And it can travel easily in snow and ice, something that could bring normal trains to a screaming stop.
28. This passage is about __________.
A. maglev B. magnets C. levitation D. electricity
29. Which of the following is a repelling action?
A. B. C. D.
30. What can we learn from the text?
A. A magnet-filled guiding way is formed inside a maglev train.
B. Instead of electricity, magnets are used as the power of a maglev.
C. Maglev trains can climb hills with the help of magnet wheels.
D. Electric currents decide the movements of a maglev train.
31. What is the difference between a maglev train and an ordinary train?
A. A maglev train can climb mountains without power while an ordinary one can’t.
B. A maglev train can travel in college campus while an ordinary train is not allowed.
C. Travelling without a track, a maglev train is safer and smoother than an ordinary one.
D. Floating on a track, a maglev train is faster, quieter than an ordinary railway train.
【回答】
ABDD
知识点:阅读理解
题型:阅读理解
-
阅读下文,根据文中的情境,选出依序最合适填入*、乙的选项。(3分)清光四*,天空皎洁, * ,坐客无...
问题详情:阅读下文,根据文中的情境,选出依序最合适填入*、乙的选项。(3分)清光四*,天空皎洁, * ,坐客无不悄然!舍前有两株梨树,等到月升中天,清光从树间筛洒而下, 乙 ,此时尤为幽绝。直到兴阑人散,归房就寝,月光仍然逼进窗来,助我凄凉。 ...
-
2003年楚人学舟楚①人有习*舟者,其始折旋②疾徐,惟舟师之是听。于是小试洲渚之间,所向莫不如意,遂以为尽*舟...
问题详情:2003年楚人学舟楚①人有习*舟者,其始折旋②疾徐,惟舟师之是听。于是小试洲渚之间,所向莫不如意,遂以为尽*舟之术。遽谢舟师,椎③鼓径进,亟犯④大险,乃四顾胆落,坠桨失柁⑤。【注释】①楚:古国名。②折:调头。旋:转弯。③椎:用椎敲。古代作战,前进时以击鼓为号。④亟...
-
_____togiveupsmoking,hethrewawayhis_______cigarettes. ...
问题详情:_____togiveupsmoking,hethrewawayhis_______cigarettes. A.Determining;remained B.Determining;remaining C.Determined;remained D.Determined;remaining【回答】D知识点:分词题型:选择题...
-
____________的建成,结束了我国靠洋油过日子的时代,社会主义探索中,涌现出来的模范人物有石油工人__...
问题详情:____________的建成,结束了我国靠洋油过日子的时代,社会主义探索中,涌现出来的模范人物有石油工人________________。【回答】大庆油田 王进喜知识点:对社会主义道路的探索题型:填空题...
相关文章
- 完成对话A:WhatcanIdoforyou,sir?B:I'mlookingforawhiteT-shirt...
- 【2019•山东淄博】Canyouimaginewalkingin,sittingnexttoastrange...
- Generally,students'innermotivationwithhighexpectationsf...
- 短文改错DearTom,I'mgladtoknowthatyouareinterestinginBeijing...
- ―I'msorry,butsmokingisnotallowedinthissectiononthetrain...
- ---I'msotiredafterthelongjourneythatIwanttogotobedatonc...
- Areyoufacingasituationthatlooksimpossibletofix?In1969,t...
- China'sbadmintonsuperstarLinDanwonathrillingfinalforhi...
- Beijing'slargestartdistrict,798ArtZone,willhostitsfirst...
- Mostdrinkstatingthattheyarefruit-flavored(水果味道的)contain...