首页
登录
职称英语
Suppose we were in a spaceship in free fall, where objects are weightless, and w
Suppose we were in a spaceship in free fall, where objects are weightless, and w
游客
2025-02-25
18
管理
问题
Suppose we were in a spaceship in free fall, where objects are weightless, and wanted to know a small solid object’s mass. We could not simply balance that object against another of known weight, as we would on Earth. The unknown mass could be determined, however, by placing the object on a spring scale and swinging the scale in a circle at the end of a string. The scale would measure the tension in the string, which would depend on both the speed of revolution and the mass of the object. The tension would be greater, the greater the mass or the greater the speed of revolution. From the measured tension and speed of whirling, we could determine the object’s mass.
Astronomers use an analogous procedure to "weigh" double-star systems. The speed with which the two stars in a double-star system circle one another depends on the gravitational force between them, which holds the system together. This attractive force, analogous to the tension in the string, is proportional to the stars’ combined mass, according to Newton’s law of gravitation. By observing the time required for the stars to circle each other (the period) and measuring the distance between them, we can deduce the restraining force, and hence the masses. [br] According to the passage, the tension in the string mentioned in lines 8-9 is analogous to which of the following aspects of a double-star system?
选项
A、The speed with which one star orbits the other
B、The gravitational attraction between the star s
C、The amount of time it takes for the stars to circle one another
D、The distance between the two stars
E、The combined mass of the two stars
答案
B
解析
Supporting idea
The second paragraph states that an attractive force is analogous to the tension in the string. This attractive force is identified in the previous sentence as the gravitational force between the two stars in a double-star system.
A The second paragraph states that the speed with which the stars circle each other depends on the gravitational force between them, but it is that force that is analogous to the tension in the string.
B Correct. The second paragraph clearly identifies the gravitational force between the two stars as the attractive force that is analogous to the tension in the spring scale’s string.
C The amount of time it takes for the stars to circle one another is necessary for calculating the force that holds them together, but it is the force itself that is analogous to the string’s tension.
D The distance between the stars must be measured if the attraction between them is to be determined, but the attraction, not the distance, is analogous to the string’s tension.
E The combined mass of the two stars is what the procedure is designed to determine; it is analogous to the mass of the small solid object, as described in the first paragraph.
The correct answer is B.
转载请注明原文地址:http://tihaiku.com/zcyy/3971705.html
相关试题推荐
Supposewewereinaspaceshipinfreefall,whereobjectsareweightless,andw
Supposewewereinaspaceshipinfreefall,whereobjectsareweightless,andw
Supposewewereinaspaceshipinfreefall,whereobjectsareweightless,andw
SupposeABCDisarectangle,Oisthecenterofthecircle.Ifthecoordinateso
SupposeABCDisarectangle,Oisthecenterofthecircle.Ifthecoordinateso
CONTEMPORANEOUS:EVENTS::A、adjacent:objectsB、modem:timesC、temporary:me
AlthoughcosmicobjectshavestruckEarthsincetheplanet’sveryformation,hum
BecausetheymakeupjustasmallpercentofallobjectsthatfalltoEarth,car
Theconsumeradvocateclaimedthatwhiledrugmanufacturers(i)______thesuppose
Thespottedbowerbirdhasa(i)______foramassingthebrightshinyobjectsitne
随机试题
Anumberofscientificstudieshavefoundthattheamountofsugarweconsum
[originaltext]Ken:Hello,Rob.Rob:Hello,Ken...HelloBarbara.Comei
两个收益完全负相关的证券组成的资产组合,最小方差资产组合的标准差是()A.0
吸人性损伤患者防治肺部感染的基本措施是A.减少医院交叉感染 B.应用抗生素
基金公司应对不相容的岗位、公司资产与客户资产执行严格的( )。研究、投资决策、
下列关于我国QFII机制的意义,说法错误的是( )。A.可以为境内金融资产提供
Thechangeinthatvillagewasmiraculou
牙防小分队进驻某小学后,与校领导和卫生老师一起研究了学校口腔保健计划,就准备开展
根据增值税法律制度的规定,增值税一般纳税人购进的下列服务,不得抵扣进项税额的有(
玻璃幕墙密封胶的施工厚度应大于3.5mm,一般应控制在4.5mm以内。密封胶的施
最新回复
(
0
)