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
The movement of the sun creates periods of________.
The movement of the sun creates periods of________.
admin
2022-04-28
24
问题
The movement of the sun creates periods of________.
W: Dr. Smith, how did early humans start to note, or record the passing of time?
M: Well, this is a long story. No one knows what time itself is. But we can notice its passing in a number of ways. In early human history, the only changes that seemed to repeat themselves evenly were the movements of objects in the sky. The most easily seen result of these movements was the difference between light and darkness.
The sun rises in the eastern sky, producing light. It moves across the sky and sinks in the west, causing darkness. The periods of light and darkness it created were the first accepted periods of time. We have named each period of light and darkness—one day.
People saw the sun rise higher in the sky during the summer than in winter. They counted the days that passed from the sun’ s highest position until it returned to that position. They counted 365 days. We now know that is the time Earth takes to move once around the sun. We call this period of time a year.
W: I am sure the moon was also very important to our ancestors.
M: Yes, of course. Early humans also developed a way to use the changing faces of the moon to tell the time.
The moon was "full" when its face was bright and round. The early humans counted the number of times the sun appeared between full moons. They learned that this number always remained the same—about 29 suns. 29 suns equaled one moon. We now know this period of time as one month.
As early humans learned to plant seeds and grow crops, they had to know when the seasons would change. So, they developed calendars. No one knows when the first calendar was developed. But it seems possible that it was based on moons, or lunar months.
The divisions of time we use today were developed in ancient Babylonia 4,000 years ago. Babylonian astronomers believed the sun moved around the Earth every 365 days. They divided the trip into twelve equal parts, or months. Each month was thirty days. Then, they divided each day into 24 equal parts, or hours. They divided each hour into sixty minutes , and each minute into 60 seconds.
Humans have used many devices to measure time. The sundial was one of the earliest and simplest. A sundial measures the movement of the sun across the sky each day. It has a stick or other object that rises above a flat surface. The stick, blocking sunlight, creates a shadow. As the sun moves, so does the shadow of the stick across the flat surface. Marks on the surface show the passing of hours, and perhaps, minutes.
W: But the sundial works well only when the sun is shining. So, what are the other ways to measure the passing of time?
M: Of course. One device is the hourglass. It uses a thin stream of falling sand to measure time. The hourglass is shaped like the number eight wide at the top and bottom, but very thin in the middle. In a true " hour" glass, it takes exactly one hour for all the sand to drop from the top to the bottom through a very small opening in the middle. When the hourglass is turned with the upside down, it begins to mark the passing of another hour.
By the 18th century, people had developed mechanical clocks and watches. And today, many of our clocks and watches are electronic.
So, we have devices to mark the passing of time. But what time is it now? Clocks in different parts of the world do not show the same time at the same time. This is because time on Earth is set by the sun’s position in the sky above.
As international communications and travel increased, it became clear that it would be necessary to establish a common time for all parts of the world.
In 1884, an international conference divided the world into 24 time areas, or zones. Each zone represents one hour. The astronomical observatory in Greenwich, England, was chosen as the starting point for the time zones. Twelve zones are west of Greenwich. Twelve are east. The time at Greenwich—as measured by the sun—is called Universal Time. For many years it was called Greenwich Mean Time.
W: That brings us to the modern time. Thanks very much, Dr. Smith.
选项
答案
Mechanical clocks / watches
解析
转载请注明原文地址:https://kaotiyun.com/show/UzPd777K
本试题收录于:
公共英语五级笔试题库公共英语(PETS)分类
0
公共英语五级笔试
公共英语(PETS)
相关试题推荐
Accordingtothespeaker,whoshouldenjoythefightofAcademicFreedom?
Accordingtothespeaker,whoshouldenjoythefightofAcademicFreedom?
Asmoreandmorematerialfromotherculturesbecameavailable,Europeanscholarscametorecognizeevengreatercomplexityinm
Internationalfreetradeoccurswhentherearenobarrierstotrade.Countriescangetalotofbenefitsfromfreetrade.(31),
Themovementofthesuncreatesperiodsof______.
What’stheaverageincreaseperyearofforeignstudentpopulationintheperiodbetween1985and1990intermsofpercentage?
What’stheaverageincreaseperyearofforeignstudentpopulationintheperiodbetween1985and1990intermsofpercentage?
AstunnedHollywooddebatedthefutureofoneofitsbiggeststarsSunday.Asasheriff’swatchdoglaunchedaninvestigationint
RecentsurveysshowthatJapaneseyouthhavebecomea"MeGeneration"thatrejectstraditionalvalues."Around1980manyJap
WhyisGriffithoftencalledTheFatheroftheMotionPicture?
随机试题
十二指肠溃疡患者近几天剧烈呕吐,呕吐物中有宿食酸臭味,查血清钾2.3mmol/L,血清钠116mml/L,血清氯化物86mmol/L,应选择下列哪项措施最好
脓液呈淡黄或淡红稀薄时常提示感染病原菌为()
A.昏迷B.心脏病C.脑膜刺激征D.三偏征E.血性脑脊液
在对房地产项目进行多因素敏感性分析时,通常假定同时变化的几个因素发生变化的概率相同,而且是()的。
设三阶方阵A的特征值为1,2,3,则|A-1|=()。
背景资料:某公路隧道为单洞双向行驶两车道隧道,全长4279m,最大埋深1049m。隧道净空宽度9.14m,净空高度6.98m,净空面积为56.45m。。该隧道其围岩主要为弱风化硬质页岩,属Ⅳ一Ⅴ级围岩,稳定性较差。根据该隧道的地质条件和开挖断面宽
不收取基金销售服务费的,对持有持续期长于6个月的投资人,应当将不低于赎回费额的()计入基金财产。
商业银行办理储蓄存款业务,应当遵循()原则。①存款自愿、存款有息;②公平对待;③取款自由;④为存款人保密
嵌入式系统的开发过程按顺序可以分成__________【77】分析与规格说明、系统设计、__________【78】设计、系统集成与测试等4个阶段,测试的目的是验证模块/系统的功能和性能,以及发现错误。
Theministerhadto______becausehewasinvolvedinthescandal.
最新回复
(
0
)