首页
登录
职称英语
[originaltext]M: Fireworks,dazzling displays,I wonder how they work?W: It actu
[originaltext]M: Fireworks,dazzling displays,I wonder how they work?W: It actu
游客
2023-09-02
68
管理
问题
M: Fireworks,dazzling displays,I wonder how they work?
W: It actually depends on a rather simple technology: an explosive mixture known as gunpowder. It shoots fireworks into the air and propels bullets from guns.
M: It was the Chinese that first discovered gunpowder, right?
W: Quite so,over 1,000 years ago. (22) The Chinese used it to make firecrackers. Marco Polo said they believed the noise had the power to scare away evil spirits.
M: Indeed,it’s such a dreadful noise,but how exactly does the black powder,gunpowder,make all those shapes and colors?
W: Aha,(23) the shapes and colors are sparks and gas and smoke produced in the process of burning,and a relatively slow one, so you can see it in the air. If it burnt too quickly it would all be over and it would be a pointless firework.
M: OK,I see.
W: The gunpowder is a mixture of three components. If you mix them together you end up with a powder in which you can still see the same particles.
M: (24) So, change the combination, and we get a different firework composition, and so on.
W: You got it fast. Now we press the powder into a cake and burn it,the fire can travel all directions and the whole reaction is very quick. This sort of thing is used for making the lifting charges of fireworks, where you want lots of gas in a short space of time.
M: (25) And if we take the powder but compress it into some other shape,say a tube,what will we get?
W: (25) Then we’ll get a little fountain. It only burns on the top surface.
22. What did the Chinese first use firecrackers for?
23. What are the colors and shapes of fireworks?
24. How do we make different colors of fireworks?
25. What will we get if we press the gunpowder into tubes?
选项
A、Lots of gas in a very short period.
B、Great lifting charges of fireworks.
C、A fountain of sparks,gas and smoke.
D、Flames burning on the top only.
答案
D
解析
对话最后,女士提到,如果将火药做成管子的形状,那么最后就会得到一个喷火的喷泉,火焰只在顶端燃烧。故答案为D)。
转载请注明原文地址:https://tihaiku.com/zcyy/2979306.html
相关试题推荐
[originaltext]TheGreatFireofLondonstartedintheveryearlyhoursof2
[originaltext]TheGreatFireofLondonstartedintheveryearlyhoursof2
[originaltext]Whatdoyouwanttobewhenyougrowup?Ateacher?Adoctor?
[originaltext]W:Haveyoueverattendedagroupinterview?Imeananinterview
[originaltext]W:Haveyoueverattendedagroupinterview?Imeananinterview
[originaltext]W:Thisapartmentconsistsoftwobedrooms,alivingroomwitha
[originaltext]W:Thisapartmentconsistsoftwobedrooms,alivingroomwitha
[originaltext]W:Thisapartmentconsistsoftwobedrooms,alivingroomwitha
[originaltext]W:Thisapartmentconsistsoftwobedrooms,alivingroomwitha
[originaltext]W:Thisapartmentconsistsoftwobedrooms,alivingroomwitha
随机试题
Today,theTowerofLondonisoneofthemostpopulartourist【1】andattracts
尽管人们对素食主义和纯素食主义的兴趣日益浓厚,但调查发现,几乎没有证据表明富裕阶层的人正在变成素食主义者。(findlittleevidencethat)
IthinkIwasatschool,______Iwasstayingwithafriendduringthevacation
Fewhumanrecordssurviveforlong,the16000-year-oldPaleolithiccavepai
建设工程图纸会审纪要的主要内容应包括()。A.设计变更 B.为便于施工,施工
A.放射状切口 B.沿皮肤自然纹理切开 C.沿乳房下缘作弧形切口 D.沿乳
心脏的正常起搏点是A.窦房结 B.房室结 C.浦肯野纤维 D.房室束 E
某集团公司审计部派出审计组,赴下属子公司对其上一年度财务收支实施的审计属于(
审计人员拟使用分析方法检查销售费用合理性,以下情况不适用分析方法的是()。A:销
材料供应商张某对工商局违法扣押其货物提起行政复议,在复议期间,工商局具体行政行为
最新回复
(
0
)