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
Weight on and off the Earth We are so used to our life on the surface of the earth that it can be quite an effort for our mi
Weight on and off the Earth We are so used to our life on the surface of the earth that it can be quite an effort for our mi
admin
2014-09-13
105
问题
Weight on and off the Earth
We are so used to our life on the surface of the earth that it can be quite an effort for our mind to break free of all the ideas that we take for granted. Because we can feel that things are heavy, we think of "weight" as being a fixed quality in an object, but it is not really fixed at all. If you could take a one-pound packet of butter 4, 000 miles out from the earth, it would weigh only a quarter of a pound.
Why would things weigh only a quarter as much as they do at the surface of the earth if we took them 4, 000 miles out into space? The reason is this; all objects have a natural attraction for all other objects; this is called gravitational attraction. But this power of attraction between two objects gets weaker as they get farther apart. When the butter was at the surface of the earth, it was 4, 000 miles from the center. When we took the butter 4, 000 miles out, it was 8, 000 miles from the center, which is twice the distance. If you double the distance between two objects, their gravitational attraction decreases two times two. If you treble the distance, it gets nine times weaker(three times three)and so on.
So this is one of the first things we need to remember that the weight of an object in space is not the same as its weight on the surface of the earth.
What about the weight of our pound of butter on the surface of the moon? At the distance the pull of the earth is about 4, 000 times smaller than it is here on the surface, so we can forget all about the earth-pull on our butter.
On the other hand, on the moon there will be an attraction between the butter and the moon, but the butter will weigh only about one-sixth as much as it does on the earth. This is because the moon is so much smaller than the earth. The amount of gravitational pull that a body produces depends on the amount of material in it. A packet of butter has a gravitational pull of its own; but this is very small in relation to the pull of something as large as the moon, or the earth, or the sun.
How much would four pounds of tea weigh if it was taken 4 , 000 miles out from the surface of the earth?
选项
A、1 pound.
B、2 pounds.
C、3 pounds.
D、4 pounds.
答案
A
解析
第一段最后一句表明,1磅重的黄油在离地球表面4 000英里处重达0.25磅,第二段第一句也表明在4 000英里高空处的物体重量仅为其在地球表面的重量的1/4。由此可推算出,4磅重的茶叶在离地球表面4 000英里处重达1磅。
转载请注明原文地址:https://www.kaotiyun.com/show/qHQd777K
本试题收录于:
职称英语理工类C级题库职称英语分类
0
职称英语理工类C级
职称英语
相关试题推荐
ManyAmericanwomenhaveapoorknowledgeofcancer.ACOG’seffortstoeducatewomenaboutcancerwillbegreatlyappreciated.
Itisoutrageousthatthesebuildingsremainemptywhilethousandsofpeoplehavenohomes.
Thousandsofpeopleperishedinthestorm.
Thousandsofpeopleperishedinthestorm.
LightNight,DarkStarsThousandsofpeoplearoundtheglobestepoutsidetogazeattheirnightsky.Onaclearnight,with
AinyourbodyBwithoutwaterCbeforelongDforachangeEonabusydayFtoyourweightTheamountofwateryourbodyneed
Featuressuchasheight,weight,andskincolordifferfromindividualtoindividualandfromfacetoface。
SaunaCeremonialbathinghasexistedforthousandsofyearsandhasmanyforms,oneofwhichisthesauna.TheFinnshavepe
SaunaCeremonialbathinghasexistedforthousandsofyearsandhasmanyforms,oneofwhichisthesauna.TheFinnshavepe
随机试题
重新点燃启蒙的火炬在告别20世纪而进入21世纪之际,中国思想界对启蒙有截然相反的看法。有人历数启蒙的罪状,劝告知识分子放弃启蒙立场;有人则回顾启蒙被压倒的悲剧,希望在中国“重新点燃启蒙的火炬”。亩对思想界的矛盾和种种困惑,有一个问题必须回答:今日
预防术后肺部感染的措施,不包括
根据《建筑安装工程费用项目组成》的规定,()不属于材料费的组成内容。
下列由省级公安部门及其授权的部门签发的是()。
景区景点导游员在讲解过程中应自觉做到()。
下面左图为我国某市城市建成区示意图,右图为该城市3个年份不同方向的建成区面积图。读图完成下题。M区为该城市的重化工业园区,其布局理由是()。
下列属于我国环境保护政策、原则的有()。
A、 B、 C、 D、 E、 A
自从有了中国共产党,中国革命的面貌就焕然一新了。因为()。
Impressionismbeganwithasmallgroupofartistswhowantedto______.Mostpeopledidnotlikeimpressionisticpainting_____
最新回复
(
0
)