问题 单项选择题

关于三相同步发电机产生对称三相交流电的下列说法错误的是()。

A.由于定子绕组空间三相对称,故三相电动势相位差互成120°

B.由于定子三相绕组切割磁力线而产生三相交变电动势

C.当定子三相绕组内有电流,而该电流又处于磁场中并受力的作用,便出现了驱动转子旋转的电磁转矩

D.严格说,只有转子磁极恒速旋转,定子绕组产生的交流电的频率才恒定

答案

参考答案:C

阅读理解

阅读理解。

     When I came to Cincinnati as an au pair (家庭打工留学生),a lot of things there were

different from what I knew.My host family lived in a huge house I could only describe as a

"castle".In Germany I had lived in a small apartment together with my mom.Soon I found

out that the "castle" was actually rather small in our neighborhood.

     Everybody there was very friendly and polite.They greeted youwhen they were walking

by at least 3 feet away from you.They must not have seen a German au pair before,for most

people I met asked me all kinds of questions about Germany.I enjoyed answering their various

strange questions.I made a lot of friends and I started to hang out with them.

     Of course,there were a numbor of new things,and it took me the whole year to find them

all out.I never got homesick.Perhaps it was because I did not have too many negative

(负面的) experiences and felt loved and welcomed there.

     However,I had undergone some painful experience back in Germany.I was frustrated

by the way people would run me over and not even say "Sorry." Taking up my studies at

the TUDresden I felt lonely.Everybody here seemed to be withdrawn(离群的)and I missed

ewerything I had in Cincinnati.Germany was so "cold".I found it so much harder to make

new friends.After six months I got a roommate and only two good friends.I also flew back to

Cincinnati several times for long periods.I felt that without those visits I was not able to make it.

Now I am over this German culture shock.It almost took me an entire year.I am still going

back and forward between Dresden and Cincinnati four times a year.

1.When the author lived in Cincinnati,________.

A.she lived in a real castle

B.some people were not very kind to her

C.many people were curious about her motherland

D.she lived in the biggest house in the neighborhood

2.In the opinion of the author,life in Cincinnati was________.

A.wonderful

B.hard

C.painful

D.strange

3.The underlined word "undergone" in Paragraph 4 probably means________

A.welcomed

B.accepted

C.expected

D.suffered

4.Which of the following statements is TRUE about the author?

A.She lived with her mother in a big house in Germany.

B.She never went back to Cincinnati after she came back to Germany.

C.She seldom hung out with her American friends as she was too busy.

D.She did miss her friends in Cincinnati when she was at the TUDresden.

5.What is the best title for this passage?

A.University life in Germany

B.My culture shock experience

C.Advantages of living in USA

D.How to be an au pair in USA

单项选择题