首页
登录
职称英语
Because of its precision, the Cepheid-variable method of correlating
Because of its precision, the Cepheid-variable method of correlating
游客
2025-02-22
35
管理
问题
Because of its precision, the Cepheid-variable method of correlating the
luminosity of Cepheid stars with those of known types of ordinary stars is one of
the most important tools that astronomers have for ascertaining distances to
Line proximate galaxies. Fortunately, Cepheids are luminous enough to be observed
(5) in other galaxies, not just in our own, such that scientists have established a
benchmark for their true brightness. One first observes a Cepheid, notes the
time span for its luminance to vary, and plots that information on an already
established graph to derive its intrinsic luminosity. Comparing intrinsic
luminosity with apparent brightness allows one to calculate the star’s distance
(10) as long as the period-luminosity relation for the star in question is first corrected
for gravitational interference, parallax, and experimental error. Data gathered
by this process would suggest that the universe is expanding, but the method is
less reliable in the nether reaches of the universe, where the crucial evidence
for cosmic expansion would likely be spotted. [br] Which of the following best describes the organization of the passage?
选项
A、A method is criticized, and an alternative is suggested.
B、An illustration is examined, and some errors are exposed.
C、An assertion is made and a procedure is outlined.
D、A series of examples is presented, and a conclusion is drawn.
E、A hypothesis is advanced, and supporting evidence is supplied.
答案
C
解析
转载请注明原文地址:http://tihaiku.com/zcyy/3968341.html
相关试题推荐
Becauseofitsprecision,theCepheid-variablemethodofcorrelating
Whiletherehavebeencountlessattemptsatcorrelatingsunspotcycl
Whiletherehavebeencountlessattemptsatcorrelatingsunspotcycl
Whiletherehavebeencountlessattemptsatcorrelatingsunspotcycl
CURSORY:A、ungainlyB、methodicalC、instantlyusefulD、immutableE、glorifiedB
Itisthemarkofaneducatedmindtorest______withthedegreeofprecisionwhi
Becauseofthe______ofalternativetherapyintheWest,Chinesephysicianshave
Adamswasso______thathisfriendsdidnotbotherto______him,becausetheypres
Becausemodernartisneithercompletelyacceptednorrejectedbycritics,their
Bookpublishinghaslongbeen______profession,partlybecause,foryoungeredi
随机试题
Don’trespondtoanye-mails______personalinformation,nomatterhowofficial
Thefollowingdeterminers(限定词)canbeusedwithbothpluralanduncountablenou
Whatisthemaintopicofthisconversation?[br][originaltext]M:Weseemtob
根管治疗的三步骤为:()A.根管扩大、根管冲洗、根管充填 B.根管预备
能够切割金属与非金属材料,且能切割大厚工件的切割方法为()。A.氧熔剂切割 B
下列哪项传染病的病原治疗首选青霉素()A.流脑 B.伤寒 C.炭疽
中性粒细胞碱性磷酸酶染色积分明显增加,临床上最常见于下列哪种疾病A.病毒感染
处方药A.根据药品的安全性分为甲、乙两类 B.可以由消费者自行判断购买 C.
A. B. C. D.
下列各项政策措施中,属于财政政策手段的有( )。A.发行国债 B.调控利率
最新回复
(
0
)