问题 选择题
如图所示,理想变压器原、副线圈的匝数比为10:1,b是原线圈的中心接头,电压表V和电流表A均为理想电表.从某时刻开始在原线圈c、d两端加上交变电压,其瞬时值表达式为u=220sin100πt(V).下列说法正确的是(  )

A.当单刀双掷开关与a连接时,电压表的示数为22V

B.当单刀双掷开关与b连接时,电压表的示数为11V

C.当单刀双掷开关与a连接,滑动变阻器触头P向上移动的过程中,电压表的示数不变,电流表的示数变大

D.单刀掷开关由a扳向b时(滑动变阻器触头P不动),电压表和电流表的示数均变大

答案

答案:D

单项选择题 A型题
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An increase in students applying to study economics at university is being attributed to (归因于)the global economic crisis awakening a public thirst for knowledge about how the financial system works.  

Applications for degree courses beginning this autumn were up by 15% this January, according to UCAS, the Universities and Colleges Admissions Service. A. spokesman for the Royal Economic Society said applications to do economics at A-level were also up.   

Professor john Beath, the president of the society and a leading lecture at St Andrews University, said his first-year lectures-which are open to students from all departments—were drawing crowds of 400, rather than the usual 250.   

“There are a large number of students who are not economics majors, who would like to learn something about it. One of the things I have done this year is to relate my teaching to contemporary events in a way that one hasn’t traditionally done. ” He added.   

University applications rose 7% last year. But there were rises above average in several subjects. Nursing saw a 15% jump, with people’s renewed interest in caters in the pubic sector(部门), which are seen as more secure in economic crisis.   

A. recent study showed almost two thirds of parents believed schools should do more to teach pupils about financial matters, and almost half said their children had asked them what was going on, although a minority of parents felt they did not understand it themselves well enough to explain.   

Zack Hocking, the head of Child Trust Funds, said: “It’s possible that one good thing to arise from the downturn will be a generation that’s financially wiser and better equipped to manage their money through times of economic uncertainty.”  

71. Professor John Beath’s lectures are ______ .  

A. given in a traditional way                 B. connected with the present situation  

C. open to both students and their parents    D. warmly received by economics  

72. Incomes in the public sector are more attractive because of their_____.   

A. greater stability     B. higher pay    C. fewer applications   D. better reputation  

73. in the opinion of most parents ______ .   

A. eccentrics should be the focus of school teaching  

B. more students should be admitted to universities  

C. the teaching of financial matters should be strengthened.   

D. children should solve financial problems themselves   

74. According to Hocking, the global economic crisis might make the youngsters_____ .   

A. wiser in money management  

B. have access to better equipment  

C. confide about their future careers  

D. get jobs in Child Trust Funds  

75. What’s the main idea of the text?  

A. Universities have received more applications.  

B. Economics is attracting an increasing numbers students  

C. college students benefit a lot from economic uncertainty  

D. parents are concerned with children’s subject selection.