试题与答案

如图所示,两根相距为l的平行直导轨ab、cd、b、d间连有一固定电阻R,导轨电阻

题型:选择题

题目:

如图所示,两根相距为l的平行直导轨ab、cd、b、d间连有一固定电阻R,导轨电阻可忽略不计;MN为放在ab和cd上的一导体杆,与ab垂直,其电阻也为R;整个装置处于匀强磁场中,磁感应强度的大小为B,磁场方向垂直于导轨所在平面(指向图中纸面内);现对MN施力使它沿导轨方向以速度v(如图)做匀速运动;令U表示MN两端电压的大小,则(  )

A.U=vBl,流过固定电阻R的感应电流由b到d

B.U=vBl,流过固定电阻R的感应电流由d到b

C.U=vBl,流过固定电阻R的感应电流由b到d

D.U=vBl,流过固定电阻R的感应电流由d到b

答案:

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参考答案:D

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题型:阅读理解

People fell in love with Elizabeth Taylor in 1944, when she acted in the movie National Velvet — the story of Velvet Brown, a young girl who won first place in a famous horse race. At first, the producers of the movie told Elizabeth Taylor that she was too short to play the part of Velvet. However, they waited for four months until three inches (英寸) added to her height. Elizabeth Taylor’s acting in National Velvet is still considered to be the best and National Velvet became Elizabeth Taylor’s first success.

Elizabeth Taylor was born in London in 1932. Her parents, both Americans, had moved to London for business. When World War II started, the Taylors moved to California, where Elizabeth Taylor started acting in movies. After her success as a child star, Elizabeth Taylor had no trouble moving into adult roles and won the Academy Award twice for Best Actress for her performance in Butterfield 8 (1960) and Who’s Afraid of Virginia Wolf? (1966).

Elizabeth Taylor is a legend (传奇人物) of our time. Like Velvet Brown in National Velvet, Elizabeth Taylor was very lucky, and she was hard-working, beautiful, famous and rich. When Elizabeth Taylor got older, she seldom acted in movies. Instead, she spent most of time on her business, and she often helped others. Several years ago, she raised more than $40 million for research and education. In March, 2011, Elizabeth Taylor died at the age of 79.

小题1:The producers didn’t let Taylor play the part of Velvet at first because ______.

A.she was not tall enough

B.she didn’t show interest

C.she was not beautiful enough

D.she did not play well enough小题2:Where did Elizabeth Taylor start acting in movies?

A.In New York.

B.In Los Angeles.

C.In California.

D.In London小题3:When did Elizabeth Taylor win her first Academy Award for Best Actress?

A.At the age of 12.

B.At the age of 28.

C.At the age of 31.

D.At the age of 34.小题4:What do you know about Velvet Brown in National Velvet?

A.She was not rich.

B.She was a famous actress.

C.She was not well-known.

D.She won first place in a famous horse race.小题5:The writer wrote this article to _______.

A.encourage us to help others

B.advise us to watch National Velvet

C.tell us how to be successful and famous

D.give us some information about a successful star

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