关于电源电动势的说法，正确的是( ) A．在某电池的电路中每通过2C的电荷量，电

发布时间：2017-05-25 08:40 │ 来源：www.tikuol.com

题型：选择题

问题：

关于电源电动势的说法，正确的是( )

A．在某电池的电路中每通过2C的电荷量，电池提供的电能是4J，那么这个电池的电动势是0.5V

B．电源的路端电压增大时，其电源电动势一定也增大

C．无论内电压和外电压如何变化，其电源电动势一定不变

D．电源的电动势越大，电源所能提供的电能就越快

考点：闭合电路欧姆定律

题型：选择题

完形填空。

     Middle school days are both fun and busy. Students spend their days in class, listening to the interesting and
  1 boring words of the teacher. They spend the short breaks running, playing, and shouting happily  2  going
back to the classroom again. But  3  should students spend their free time outside school?
     In Western countries, it is ordinary for students to have a part-time job after school. And at weekends
students can make their own money and learn more about the " 4  world". They enjoy the independence (独立)
and (of course) money, and parents enjoy the quiet house. 5 , it seems that, in China, parents  6  so much about
their children's studies that they would prefer to see their children  7 . most of their free time studying and
preparing for all those exams. It is natural for  8 to feel that way in China, but I believe the answer lies in balance (平衡). Sometimes, Western school children work long hours after school to make money, and so they become
too tired to listen in class or have no time for homework. But Chinese students spend  9  much time on their
studies that all else becomes less important until they want that new MP4 player.
     So, find a good and healthy balance! If you have a part-time job, you'll be 10 , and your parents will also be
happy because you're spending the money you make and not theirs!

( )1. A. always
( )2. A. while
( )3. A. where
( )4. A. true
( )5. A. Because
( )6. A. know
( )7. A. spending
( )8. A. students
( )9. A. such
( )10. A. happy

B. sometimes
B. after
B. what
B. real
B. And
B. talk
B. using
B. teachers
B. so
B. tired

C. forever
C. before
C. why
C. developing
C. However
C. worry
C. taking
C. children
C. very
C. nervous

D. even
D. without
D. how
D. developed
D. Although
D. complain
D. keeping
D. parents
D. too
D. busy

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A.参附汤合生脉散

B.无比山药丸

C.补中益气汤

D.十全大补汤

E.回阳救逆汤

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A.血常规

B.电解质

C.脑脊液

D.脑电图

E.头颅CT

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1140V设备使用的电缆必须用带有屏蔽的橡套绝缘屏幕电缆。（）

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