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
Forces other than damaging winds are also at work inside tornadoes. Sometimes, as the twisting funnel passes over a house, the w
Forces other than damaging winds are also at work inside tornadoes. Sometimes, as the twisting funnel passes over a house, the w
admin
2009-08-15
40
问题
Forces other than damaging winds are also at work inside tornadoes. Sometimes, as the twisting funnel passes over a house, the walls and ceiling burst apart as if a bomb had gone off inside. This explosion is caused by the low air pressure at the center of a tornado.
The pressure at the center of a tornado is usually 13 pounds per square inch. However, inside the house the air pressure is normal, a bout 15 pounds per square inch. The difference of 2 pounds per square inch between the inside and outside pressure may not seem like much. But suppose a tornado funnel passes over a small building that measures 20 by 10 feet. On each square inch of the building, there is 2 pounds of pressure from the inside that is not balanced by air pres sure outside the building. On the ceiling, that adds up to an unbalanced pressure of 57 600 pounds. The pressure on the four walls adds up to 172 800 pounds.
If windows are open in the building, some of the inside air will rush out through them. This will balance the pressure inside and out side the building. But if the windows are shut tightly, the enormous inside pressure may cause the building to burst. Unfortunately, heavy rain and hail often occur in thunderstorms that later produce tornadoes. So people frequently shut all windows to protect their property. This may cause far worse damage later. For the same reason, tornado cellars must have an air vent. Otherwise, the cellar door might be blown out when a tornado passes over it.
选项
A、Why Tornadoes Cause So Much Damage
B、Where Tornadoes Arc Formed
C、How Tornadoes Can Be Prevented
D、When Tornadoes Usually Occur
答案
A
解析
文章的主题是从屋内外气压的差别来解释龙卷风为什么能产生如此大的危害。所以选A。
转载请注明原文地址:https://kaotiyun.com/show/jEfd777K
本试题收录于:
公共英语二级笔试题库公共英语(PETS)分类
0
公共英语二级笔试
公共英语(PETS)
相关试题推荐
Treasurehunts(寻宝)haveexcitedpeople’simaginationforhundredsofyearsbothinreallifeandinbookssuchasRobertLouis
TomBrennanwasworkinginaPhiladelphiaofficebuildingwhenhenoticedablackbag.Thebagcontainedabook.Thischance
MoreandmorepeopleinBritainarebuyingorganicfoodbecause______.Whatisthebesttitleforthisnewsstory?
AsmorewomenintheUnitedStatesmoveuptheprofessionalladder,morearefindingitnecessarytomakebusinesstripsalone.
【B1】【B20】
Thispassageismainlyaboutthat______.Whichofthefollowingsentenceistrue?
PresidentBushsaidUSforceswillremaininIraquntil______.
WhyareAmericanbillsorpapermoneyunlikethatinmanyothercountries?
Mostpeoplefeellonelysometimesbutitusuallyonlylastsbetweenafewminutesandafewhours.Thiskindoflonelinessisno
Nancysometimeswishesthatshe______inasmalltown.
随机试题
男性,35岁。急性胆囊炎。该患者的体位是
毫微囊主要应用在
男婴,4个月,冬季出生,因夜惊多汗,烦躁易哭1个月来院门诊,生后母乳喂养,未加辅食。体检:精神尚可,枕秃,枕骨按之有乒乓球感。在此患儿可能的致,病原因中,以下哪项不正确
一般药物干燥温度不宜超过含芳香挥发性成分的药物干燥温度不宜超过
A.限于一名患者的用药B.应当在修改处签名并注明修改日期C.单独开具处方D.分别开具处方,也可以开具一张处方E.每一种药品应当另起一行,每张处方不得超过5种药品每张处方
用可调工料单价法计算工程进度款时,其基本步骤有()。
教师讲解“所以动心忍性,曾益其所不能”中“所以”的词义,另举一例加以说明,下列合适的是()。
“明月出天山,苍茫云海间”是李白的著名诗句,我们根据该诗句可以推断:
所有与甲流患者接触的人都被隔离了,所有被隔离的人都与小王接触过。如果以上命题为真,以下哪个命题也是真的?()
YouwillhearaninterviewwithHarryStyles,theGeneralManagerofFourSeasonsHotelPhiladelphia.Foreachquestion(23-3
最新回复
(
0
)