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
A Canadian researcher has discovered that sound travels 【21】______ air more than one-haft kilometer an hour slower than had been
A Canadian researcher has discovered that sound travels 【21】______ air more than one-haft kilometer an hour slower than had been
admin
2010-06-30
55
问题
A Canadian researcher has discovered that sound travels 【21】______ air more than one-haft kilometer an hour slower than had been believed. The discovery has surprised many engineers and scientists who learned they had been 【22】______ the wrong speed of sound for many years.
The speed of sound in air had been 【23】______ to be three-hundred-thirty-one-point-two-nine meters a second. But Doctor George Wong found, 【24】______ accident, that the speed of sound is only three-hundred-thirty-one-point-one-three meters a second. That is a difference of about sixteen centimeters a second.
Doctor Wong is a member of the National Research Council of Canada. He was studying ways to 【25】______ exactly the sound created by microphones. One of his experiments 【26】______ a number he could use to find the speed of sound. He was 【27】______ to learn that the speed of sound was slower than scientists had thought.
To explain the difference, Doctor Wong spent eighteen months 【28】______ past test research on the speed of sound. He finally found the 【29】______ of the difference. It was a mathematics mistake 【30】______ in Nineteen-Forty-Two by physicist H-C Hardy.
Doctor Wong’s 【31】______ does not mean a big change for the science of sound. This is 【32】______ Doctor Hardy and Doctor Wong measured the speed of sound for what is called " standard air".
Standard air exists only 【33】______ thought. It is a way for scientists to agree 【34】______ the same speed of sound. 【35】______ the air around us, standard air always has a temperature of zero degrees Celsius and the same atmospheric pressure 【36】______ the air at sea level. Standard air al ways have same amounts of nitrogen, oxygen, carbon dioxide and 【37】______ gases. And in standard air, the speed of sound does not change.
The change in the new speed of sound is 【38】______ small to affect the work of most sound scientists and engineers. But scientists say Doctor Wong’s discovery may 【39】______ improve instruments 【40】______ use the speed of sound to measure very short distances.
【29】
选项
A、resource
B、source
C、origin
D、reason
答案
D
解析
本句意为“他最后找到了产生区别的原因”。A“资源”;旷来源”;C“起源、由来”,均不合题意。只有D项“理由,原因”正确。
转载请注明原文地址:https://www.kaotiyun.com/show/sxJd777K
本试题收录于:
公共英语四级笔试题库公共英语(PETS)分类
0
公共英语四级笔试
公共英语(PETS)
相关试题推荐
Ifyou’vebeenoncampusforverylong,I’mcertainthatyou’vealreadyheardaboutthiscourse.Youmayknowthatlastsemester
Periodicallyinhistory,therecomeperiodsofgreattransitioninwhichworkchangesitsmeaning.Therewasatime,perhaps10,
Themostobviouspurposeofadvertisingistoinformtheconsumerofavailableproductsorservices.Thesecond【C1】______istos
Payandproductivity,itisgenerallyassumed,shouldberelated.Buttherelationshipseemstoweaken【C1】______peoplegetolder
Fordecades,postersdepictingrabbitswithinflamed,reddenedeyessymbolizedcampaignsagainstthetestingofcosmeticsonani
FewwritersareasreveredasJaneAusten.AccordingtoapollinMarch,PrideandPrejudice—aromancewithoutasinglekiss—is
WhendidKantbecomeaprofessor?
WhendidKantbecomeaprofessor?
【B1】Swedenhasgotapopulationofonly8million,butitisalargecountrywithanareaof450,000squarekilometers.【B2】The
【B1】Swedenhasgotapopulationofonly8million,butitisalargecountrywithanareaof450,000squarekilometers.【B2】The
随机试题
全面质量管理的基本内涵。
抢救由心室纤颤引起的心脏骤停时,最有效的方法是
治疗羊水过多的药物是
Y企业2010年发生亏损,且以前年度亏损仍未弥补完,但当年仍可以向投资者分配利润。()
Generallyspeaking,customersinteractwith______.
针对对应数据的列报与披露事项,以下说法中,不恰当的是()。
法律关系是指由一国现行的全部法律规范按照不同的法律部门分类组合而形成的一个呈现体系化的有机联系的统一整体。()
(2013年真题)甲午夜开车送朋友乙回家,因超速驾驶,刹车不及时,将经过人行横道的周某撞倒。乙对甲说:“没有人看到,快走。”甲加速离去。周某随即被他人送往医院,但因抢救无效,于当晚死亡。甲将乙送回家后,心里不安,便返回肇事地点,并向在事故现场取证的警察交代
(1)TheChildrenAct1989doesnotassuchrequireparentsorpersonsholdingparentalresponsibilitytoeitherinvolvechildren
Itmaybeoneoftheworld’sgreatshoppingdestinations,butLondon’sRegentStreetisfailingthefashiontest,accordingtot
最新回复
(
0
)