问题 选择题

空间某一静电场的电势Φ在x轴上分布如图所示,x轴上两点B、C点电场强度在x方向上的分量分别是EBxECx,下列说法中正确的有(  )

A.EBx的方向沿x轴正方向

B.EBx的大小大于ECx的大小

C.电荷在O点受到的电场力在x方向上的分量最大

D.负电荷沿x轴从B移到C的过程中,电场力先做负功,后做正功

答案

A  B点沿X轴的反方向电势变小,则EBx沿X轴负方向.故A错

 B 在B点电势降低的快,则B点场强大.故B正确

       C 电势高的地方,场强不一定大.故C错误

       D  负电荷由B到C,电场力选做正功,后做负功.故C错误

故选:B

阅读理解

Directions: Read the following three passages. Each passage is followed by several questions or unfinished statements. For each of them there are four choices marked A, B,C and D. Choose the one that fits best according to the information given in the passage.

A

Food

British people like good food, and more than half of them go to a restaurant every month. Fast food is also very popular---30% of all adults have a hamburger every three months, but 46% have fish and chips!

Sports

British people don’t do a lot of sports. Only 17% of people go swimming every week, about 9% go cycling and 8% play golf--- and only 6% of people play football (but 32% go to watch it).

Cinema and TV

Films are very popular in Britain, and about 60% of the young people go to the cinema every month. At home, men watch TV for about three hours every day ---30 minutes more than women.

Holidays

British people love going on holiday, and have 56 holidays every year. Most of these holidays aren’t spent in the UK---27% are in Spain. 10% are in the USA, and 9% are in France. Maybe this is because the weather in Britain isn’t very good!

Presents

British people don’t send others expensive presents like other Europeans. They often send chocolates, wine and flowers of good quality.

小题1: Which food could be more popular among British adults, a hamburger or fish and chips?

A.A hamburger.

B.Fish and chips.

C.Both.

D.Neither.小题2:Those who are interested in movies are _____.

A.men

B.women

C.young people

D.old people小题3:How long do British women spend watching TV every day?

A.Three hours.

B.Three hours and a half.

C.Two hours.

D.Two hours and a half.小题4: British people’s favorite country for a holiday is _____.

A.Spain

B.France

C.America

D.Australia小题5: What present don’t British people often send?

A.Chocolates.

B.Wine.

C.Flowers.

D.Money.

单项选择题