试题与答案

如图所示,平行金属导轨与水平面成θ角,导线与固定电阻R1和R2相连,匀强磁场垂直

题型:选择题

题目:

如图所示,平行金属导轨与水平面成θ角,导线与固定电阻R1R2相连,匀强磁场垂直穿过导轨平面.有一导体棒ab,质量为m,长度为L,导体棒的电阻与固定电阻R1R2的阻值相等,都等于R,导体棒与导轨之间的动摩擦因数为μ,导体棒ab沿导轨向上滑动,当上滑的速度为v时,有

[ ]

A.棒中感应电流的方向由ba      

B.棒所受安培力的大小为

C.棒两端的电压为

D.棒动能的减小量等于其重力势能的增加量与电路上产生的电热之和

答案:

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参考答案:A, B, C, D, E

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题型:阅读理解

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What do you see from a handful of seeds? Some see green plants, some see blooming flowers, or just seeds. But one group of Shanghai students saw an opportu­nity to make money.

Eight students from No 2 Secondary School Attached to East China Normal Uni­versity started a virtual company selling different seeds and seed products. They successfully sold 28 pictures pasted with different seeds at a campus auction a week a­go. The company, which has recruited around 20 student staff members, has earned over 2000 yuan in the past three months.

"We donated part of the money to a poor school in the countryside of Anhui Province. It's great to realize our ideal of ‘spreading love and culture with seeds’ after many tests and lots of hard work," said Senior 2 Shi Chen, CEO of the compa­ny.

Just like any other company, Shi's didn't develop smoothly. Shi and her young colleagues used to sell fresh flowers and old books, and later found seeds might be something that their company could engage in. They bought seeds of various plants and flowers at low prices from a local farm and sold them in schools or on streets. The creative students also made accessories and pictures with different seeds.

With little business knowledge, the students had to learn new skills as the lead­ers of different departments, such as public relations (PR), sales and marketing. They persuaded a joint Sino-French company near their school to give them training in business management. They also asked some local businessmen to act as their consul­tants.

"They helped us overcome our shyness. We also learned quite a lot of business theory. I found communication skills and teamwork are very important for my job," said Senior 1 Qian Yifei.

The 16-year-old was elected as PR manager thanks to her talent for speaking. She is also in charge of after sales service, dealing with complaints and providing suggestions.

As the head of the company, CEO Shi has a lot more to think about. First of all, she has to learn how to make her colleagues work efficiently as the company only opens at weekends due to all their studies. So she established a system to evaluate every one's performance, in terms of punctuality, efficiency, profits knowledge and so on.

"It makes the company more formal," she said.

59. What is the purpose of opening the company?

A. To earn money for their education fees.

B. To spread love and culture with seeds.

C. To see whether they can open a company.

D. To collect money to open a Hope School.

60. At a campus auction a week ago, they ________ .

A. sold 28 green plants with different flowers

B. sold 28 seeds pasted with different pictures

C. sold 28 pictures pasted with different seeds

D. sold 28 flowers pasted with different pictures

61. According to Qian Yifei, what matters most in dealing with public relations?

A. Communication skills and teamwork.

B. Creative and critical thinking.

C. Educational background.

D. Business theories.

62. What does the word "it" (in the last paragraph) refer to?

A. Selling seeds.

B. To have a person as CEO.

C. Every colleague’s performance.

D. To make her colleagues work efficiently.

63. What can we learn from the passage?

A. The company is owned by 8 students.

B. The company is over-night successful.

C. The company gets a lot of help from others.

D. The company sells old books and fresh flowers.

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