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
During the early period of the earth’ s history, the weather on earth apparently fluctuated between bright sun and showers. In r
During the early period of the earth’ s history, the weather on earth apparently fluctuated between bright sun and showers. In r
admin
2010-01-07
86
问题
During the early period of the earth’ s history, the weather on earth apparently fluctuated between bright sun and showers. In recent times, however, the mountains and valleys on land and under water have had a great influence on the earth’ s weather. They effect the movements of the thin film of water we call the sea and the thin layer of air around the earth. These movements produce changes in the temperature and humidity prevailing at the surface.
Although the sun is approximately 93 million miles away, its rays warm the earth. The areas that receive the sun’ s rays vertically are, naturally, warmer than those areas that receive only slanting raya. 【B1】
Vertical rays do not need to make as long a journey through the atmosphere before reaching the surface of the earth.
Therefore, less of their heat is lost in the air and more of their heat is saved to warm the earth. Furthermore, slanting rays are spread over available at a given point.
The sun’ s rays do not heat the vast stretches of space between the sun and the earth. 【B2】
If they did, we should expect to be warmer on top of a high mountain or riding in an airplane than we are on the ground.
Actually, however, we feel cooler at the top of a mountain; and, if we fly a plane high enough, we encounter freezing temperatures, even over the equator.
This is true because the sun’ s rays are like the waves used in radio broadcasting. Music sent out by a radio transmitter does not fill the air with sounds for all to hear. Instead, the music travels in the form of electromagnetic waves, which must pass through a receiver and an amplifier to be heard. 【B3】
Similarly, the sun’ s rays cross our atmosphere and are absorbed by the surface of the earth. These rays warm the surface, which sends back some of this heat into the air.
When the air near the earth’ s surface has been warmed, it rises and is replaced by cooler air which comes down to take its place. This cool air, in turn, is warmed and rises to be replaced by more cool air. As air rises it becomes cooler because it expands and is less concentrated, the air is suddenly let out of a tire, the air expands rapidly and becomes much cooler. On the other hand, when air is put under greater pressure, it becomes warmer. This is what happens to the cold air that comes down to take the place of rising warm air.
The earth is much cooler than the sun, and the wave length of the earth’ s radiations is much longer than that of sun rays. 【B4】
These longer heat waves cannot pass through the atmosphere as easily as the short waves coming from the sun.
【B5】
Similarly, radio stations that transmit programs to distant countries broadcast in short waves, which can travel all round the world.
Stations that broadcast local programs send out longer waves, which can be received more easily, but only in a limited area.
选项
答案
这些较长热波,就不如太阳发出的短波那样容易穿过大气层了。
解析
转载请注明原文地址:https://kaotiyun.com/show/GvPd777K
本试题收录于:
公共英语四级笔试题库公共英语(PETS)分类
0
公共英语四级笔试
公共英语(PETS)
相关试题推荐
HostilitytoGypsieshasexistedalmostfromthetimetheyfirstappearedinEuropeinthe14thcentury.TheoriginsoftheGyps
BetweentheendoftheWorldWarIIandtheearlysixties,ababyboomoccurredintheUS,andpeoplebornduringthatperiodwe
BetweentheendoftheWorldWarIIandtheearlysixties,ababyboomoccurredintheUS,andpeoplebornduringthatperiodwe
Vicky—beautiful,talented,verybright,voted"MostLikelytoSucceed"incollege—gotapromisingjobwithalargecompanya
Vicky—beautiful,talented,verybright,voted"MostLikelytoSucceed"incollege—gotapromisingjobwithalargecompanya
ToproducetheupheavalintheUnitedStatesthatchangedandmodernizedthedomainofhighereducationfromthemid-1860’sto
IfyouarebuyingapropertyinFrance,whetherforapermanentoraholidayhome,itisimportanttoopenaFrenchbankaccount
DoesthepublisherofDouglasStarr’sexcellentBlood—AnEpicHistoryofMedicineandCommerceactuallyexpecttosellmanycopi
Periodicallyinhistory,therecomeperiodsofgreattransitioninwhichworkchangesitsmeaning.Therewasatime,perhaps10,
随机试题
全面结算会员期货公司的期货保证金账户应当与其自有资金账户相互独立、分别管理。()
妊娠中晚期的常见症状除外
心源性休克的病理生理改变是
党的十八大报告首次将党的建设内容列入新的目标要求。()
某市寻找适合工业布局的地点,该工厂要满足两个条件:(1)地形平坦;(2)距河流1千米范围内。下图空间布局是城市地形与河流的空间分布,每一小方格代表1平方千米(该区面积共16平方千米);属性资料是地形和河流的类别资料。根据选址条件,对照空间资料和属性资料,符
下列关于诗词句作者,正确的一项是()。
农产品补贴通常是指一国政府对本国的农业产品生产商或者经营者提供资金或财政上的支持,包括现金补贴、价格支持或其他政策优惠待遇,使其农业产品在国际、国内市场上与未受补贴的同类产品相比获得竞争优势。根据上述定义,下列属于农产品补贴的是:
在H国(实行一夫一妻制)2000年进行的人口普查中,婚姻状况分为四种:未婚、已婚、离婚、丧偶。其中,已婚分为正常婚姻和分居;分居分为合法分居和非法分居;非法分居指分居者与人非法同居;非法同居指无婚姻关系的异性之间的同居。普查显示,非法同居的分居者中,女性比
Wenowcometothevitaltopicofmoney.First,wemustrememberthatscience,onanysignificantscale,existsonlyineconomie
Whichofthefollowingunderlinedpartsisapredicativeclause(表语从句)?
最新回复
(
0
)