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
47
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.
【33】
选项
A、on
B、among
C、in
D、with
答案
C
解析
in thought意为“在思想中,在想象中”。
转载请注明原文地址:https://kaotiyun.com/show/ODJd777K
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,
Payandproductivity,itisgenerallyassumed,shouldberelated.Buttherelationshipseemstoweaken【C1】______peoplegetolder
Payandproductivity,itisgenerallyassumed,shouldberelated.Buttherelationshipseemstoweaken【C1】______peoplegetolder
Fordecades,postersdepictingrabbitswithinflamed,reddenedeyessymbolizedcampaignsagainstthetestingofcosmeticsonani
YouwillhearaconversationbetweenMissGreen,aneducationaljournalist,andProfessorWilson,anexpertineducationalstudi
YouwillhearaconversationbetweenMissGreen,aneducationaljournalist,andProfessorWilson,anexpertineducationalstudi
A、AllTVsetscanreceivesomeprogramswithoutpayingmoneyinacertainarea.B、Youmaypayforsomespecialprogramsifyoul
Periodicallyinhistory,therecomeperiodsofgreattransitioninwhichworkchangesitsmeaning.Therewasatime,perhaps10,
Whenwerethefirstx-raysdiscovered?
随机试题
根据美国学者波特的研究,一个行业内部的经营状况取决于()。
下列不同性质的药物最常采用的粉碎办法是A、易挥发、刺激性较强药物的粉碎B、比重较大难溶于水而又要求特别细的药物的粉碎C、对低熔点或热敏感药物的粉碎D、混悬剂中药物粒子的粉碎E、水分小于5%的一般药物的粉碎水飞法
甲、乙、丙经事先商议,欲前往某办公大楼盗窃29寸彩电一台。商议后某日在该大楼下班后,三人一起前往。盗得彩电后,由甲乙两人装入纸箱,一人一边用手抬下楼。丙因空手,便抢先下楼。丙走至大楼门口,恰逢大楼值班员老头丁从旁边厕所走出准备打扫卫生。见丙形迹可疑,大吃一
()是我国的货币政策最终目标。
两用物项和技术许可证跨年度使用时,在有效期内只能使用到次年( )。
在注册制发行制度下,发行人只要充分披露了有关信息,在注册申报后的规定时间内未被证券监管机构拒绝注册,即可进行证券发行,无须再经过批准。( )
商品流通企业最高层次的战略是()。
毛泽东思想的活的灵魂包括:
2012年4月末,人民币贷款余额57.93万亿元,同比增长15.4%,分别比上月末和上年同期低0.3和2.1个百分点。分部门看,住户贷款增加1421亿元,其中,短期贷款增加793亿元,中长期贷款增加628亿元:非金融企业及其他部门贷款增加5351亿元,其中
Hereissomeadviceonfoodshopping.The【1】familyspendsaboutone-sixthofitsincome【2】food.Becausefoodisexpensive,iti
最新回复
(
0
)