首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
A、They travel deep inside the earth. B、They travel slow inside the earth. C、They are too small to be felt. D、They travel too fas
A、They travel deep inside the earth. B、They travel slow inside the earth. C、They are too small to be felt. D、They travel too fas
admin
2019-03-17
99
问题
Moderator: Good morning, class. Today Professor Liu will give us a lecture about earthquakes. Welcome.
Professor Liu: Thank you. As you know, some earthquakes are not powerful enough to be felt on the earth’s surface while in others, people can, indeed, feel the earth shaking. And of course, there might be violent movement, often with catastrophic results. What we feel during an earthquake or huge explosion are a series of waves called seismic waves.
In an earthquake, you might initially feel some minor trembling, then perhaps violent shaking, and then some more tremors. [16] The reason why you feel these different types of movement is because there are different kinds of seismic waves. There are two major types of seismic waves: body waves and surface waves.
The waves that you feel first are body waves. These mainly travel deep through the earth’s interior rather than at the surface. Some of them travel very fast, and that’s why you feel them first. [17] But because they travel deep inside the earth, they’re felt only as tremors. There are two types of body waves. The first type of body wave is the P wave or primary wave. It’s the fastest kind of seismic wave. These waves can move through any type of material, including rock and fluids. Because of this and because of their speed, these waves are the first to reach the earth’s surface. You likely won’t even hear or feel these waves, but animals may hear them. They’re not strong enough to cause significant damage. The other type of body wave is the S wave or secondary wave. Because S waves travel at half the speed of P waves, you won’t feel them in the beginning.
[18-1] Unlike body waves, surface waves move at or near the earth’s surface. These waves are similar to ripples on water. [18-2] They are usually the most destructive type of seismic wave because of their lower frequency, larger amplitude, and longer duration. There are two types of surface waves. The first kind of surface wave is called a love wave. It’s the fastest surface wave. The other kind of surface wave is the Rayleigh wave. It rolls along the ground just like a wave rolls across a lake or an ocean. As a result, it moves the ground up and down and side to side in the same direction that the wave is moving. [19] Most of the shaking felt from an earthquake is due to the Rayleigh wave, which can be much larger than the other waves. They are slower than body waves, and sometimes cars might appear to be moving up and down with these waves.
Questions 16 to 19 are based on the recording you have just heard.
16.Why do we feel different types of movement in an earthquake?
17.Why do we feel body waves only as tremors?
18.What are the most destructive type of seismic wave?
19.Which seismic wave brings us shaking felt from an earthquake?
选项
A、They travel deep inside the earth.
B、They travel slow inside the earth.
C、They are too small to be felt.
D、They travel too fast to be felt.
答案
A
解析
转载请注明原文地址:https://kaotiyun.com/show/sdH7777K
0
大学英语六级
相关试题推荐
Wemightbelivingforlongerthanever,butwearesick.About95percentofpeoplehaveatleastonehealthcomplaint,witha
Geothermal(地热的)energyhasbeenusedforthousandsofyearsinsomecountriesforcookingandheating.Itissimplypowerderived
A、1.96million.B、19.6million.C、1.97million.D、19.7million.A录音最后提到,根据BBC的描述,在英国上大学的学生人数在近代历史上第一次下降,从2007年的197万下降至去年(2008年)的
A、Lookthroughhermaterials.B、Makepreparationfortheinterview.C、Payattentiontothepresentation.D、Addsomethingtomake
A、Itisdesignedforjuniorschoolstudents.B、Itcontainsdifferentsubjectsexceptmaths.C、Eachcoursetakes40hourstocomp
Widespreadadoptionofplug-inelectricvehiclescoulddramaticallycutgreenhousegaspollutionandreduceU.S.dependenceonf
A、Bytravellingwithawoman.B、Bywaitinginaqueue.C、Bymeetingdifferentpeople.D、Bygivingothersahand.A女士问男士如果他跟一个女的旅
AremarkablethinghappenedinNewYorkrecently:thestatelegislature,ineffect,turneddownthechancetowin$700millioni
A、Lookedforcaves.B、Burnedtrees.C、Wenttothesea.D、Builtwoodenhouses.D女士说:“在一些气候比较温暖的地方,冰河时期的人确实建了木屋。”D符合对话中的意思。
A、$50.5million.B、$15.5million.C、$50.5billion.D、$15.5billion.B选项都与数字有关。题目问的是美国国立卫生研究院为这个研究小组提供多少资金。文中提到为了建造这个扫描仪,美国国立卫
随机试题
(2013年4月,2007年4月)人力资源管理的前提与主要职能是_______。
Manypeoplethinkofcrisisasbeing【B1】______onlywithunhappyorunpleasantevents.Thisisnotthe【B2】______.Crisiscanoccu
能治疗牙痛病证的药物是
该患者最大可能为最合适的处理方式为
下面关于胃食管反流病的说法正确的是
患者,女,22岁。用大黄通便长达1个月,导致次月的月经量过多,经期过长。上述症状属于()
对于持续持有期少于30日的投资人,基金管理人可以在基金合同中约定收取不低于赎回金额0.75%的赎回费。()
下列项目中,属于其他业务成本核算内容的有()。
如何评价软件的质量一直是软件技术人员所关心的问题,目前已有多种软件质量模型来描述软件的质量特性。ISO/IEC 9126是国际标准化组织在1991年提出的软件质量标准。它由三个层次组成,第一层是质量特性,第二层是质量子特性,第三层是度量指标。6个质量特性是
Isuggestedheshould____________(学会适应新的环境).
最新回复
(
0
)