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
Because we can feel that things are heavy, we think of weight as being a fixed quality of an object, but it is not really fixed
Because we can feel that things are heavy, we think of weight as being a fixed quality of an object, but it is not really fixed
admin
2015-05-21
62
问题
Because we can feel that things are heavy, we think of weight as being a fixed quality of an object, but it is not really fixed at all. If you could take a one-pound packet of butter 4, 000 miles out away 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 centre (in other words the radius(半径) of the earth is 4, 000 miles). When we took the butter 4, 000 miles out, it was 8, 000 miles from the centre, which is twice the distance.
If you double the distance between two objects, their gravitational attraction decreases four times weaker (two times two). If you treble(翻三倍)the distance, it gets nine times weaker (three times three). If you take it four times as far away, it gets sixteen times weaker (four times four) and so on.
选项
答案
解析
转载请注明原文地址:https://kaotiyun.com/show/UCud777K
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
Helenlookedatthefinishedpaintingwith______.
Mrs.Wilsonworksmoreslowlythantheothersecretariesbecauseshetakespride______everythingthatshedoes.
Theconceptofpersonalchoiceconcerninghealthisimportantbecause______.To"liveacompletelysedentarylife-style"(Para
Whatdidthewomanplayyesterdayafternoon?
______eachsmokeabout4,195cigarettesayear.Mostdoctorsandresearchworkersadvisethat______.
Formanypeopletoday,readingisnolongerrelaxation.Tokeepuptheirworktheymustreadletters,reports,tradepublication
Thelakelaybeforeme,blueandpeaceful,intheevening【36】.Oneithersidethemountainsrosesharplysurroundingitinakin
Heinsistedthathisbrother______thewindow.Itwasclearthatsomeoneelsebrokethewindow.
Scottandhiscompanions(同伴)wereterriblydisappointed.WhentheygottotheSouthPole,theyfoundtheNorwegians(挪威人)hadbea
Wheredoesthisinterviewtakeplace?
随机试题
作品充满地域文化色彩,被称为味十足的市井文学作家是( )
治疗湿温,暑湿,湿热胸闷、黄疸、泻痢、淋痛、疮疡治疗热病后期伤阴,阴虚发热,内热消渴
公开招标与邀请招标在招标程序上的主要不同是()。
某地开展假冒伪劣消防产品专项整治行动。检查人员在检查中发现,有些商家的消防产品存在不同程度的缺陷。根据《产品质量法》的规定,下列说法错误的是()。
中国证监会及其派出机构对期货公司及其营业部作出的整改通知、监管措施和行政处罚等,期货公司应当书面通知全体股东。( )
纳税人销售不动产时,应当向()主管税务机关申报纳税。
高尔霍夫尔提出了以生物学为基础的尊重儿童运动需求的_______。
TheXinhuabookstorechain,China’slargestofficialpublishingenterprise,hasbecomeasurprisingflashpointforinterestamo
我国的社会主义改造是一场伟大的社会变革,但是在改造过程中也出现了一些偏差,遗留了一些问题,集中表现在()
RussiaisthelargesteconomicpowerthatisnotamemberoftheWorldTradeOrganization.Butthatmaychange.LastFriday,the
最新回复
(
0
)