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
69
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://www.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
[originaltext]M:Hello.Ineedtotalkwithsomeoneaboutmydriver’slicense.
[originaltext]Mr.Fosterstartedhispublishingbusinesswithonlyonemaga
大学生恋爱与性心理的困扰以及如何进行心理调适。
关于下颌升支边缘性骨髓炎X线表现下属哪项是错误的A.CT横断面图像可显示骨膜下成
万古霉素属于A.β-内酰胺类 B.林可酰胺类 C.糖肽类 D.多黏菌素类
一个有效的绩效管理系统是通过()环节提高员工工作绩效从而保持和增强企业的竞争优势
根据《期货从业人员管理办法》,机构应当为其任用的人员办理从业资格申请,被任用者应
预应力筋在制作的时,下料长度应通过计算确定,计算时应考虑的因素有( )。A.孔
以下关于门的计量规则说法不正确的有()。A.所有门都可以采用数量计量 B
男,40岁,头痛、头晕1年,1周来加重伴心悸、乏力、鼻出血及牙龈出血来诊。查体:
最新回复
(
0
)