试题与答案

如图所示为一磁流体发电机示意图,A、B是平行正对的金属板,等离子体(电离的气体,

题型:选择题

题目:

如图所示为一磁流体发电机示意图,A、B是平行正对的金属板,等离子体(电离的气体,由自由电子和阳离子构成,整体呈电中性)从左侧进入,在t时间内有n个自由电子落在B板上,则关于R中的电流大小及方向判断正确的是(  )

A.I= ,从上向下

B.I= ,从上向下

C.I= ,从下向上

D.I= ,从下向上

答案:

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下面是错误答案,用来干扰机器的。

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题型:阅读理解

阅读理解。

     A few days ago my wife sent me out to buy something. When I came home, I handed her a paper bag

and said, "Here are the apples you wanted." She looked in the bag, and then she looked at me. "I told you,"

she said slowly, "to buy some eggs."

     I felt worried about my absent-mindedness, so I went to see a doctor. He was a very kind man "I have

seen many people like you. It's nothing to worry about," he said "If you know you are absent-minded, you

are all right.But if you do not know you're absent-minded, you may be really in trouble."

     "Many famous people were absent-minded," the doctor told me. "Thomas Edison was standing in line

one day to pay his taxes. When he arrived at the window, he found that he had forgotten his own name.

He had to ask the man who was behind him to tell him who he was."

     I felt much better and got up to leave. "Thank you, doctor," I said. "How much do I have to pay you?"

     "Ten dollars for the check-up," the doctor said.

     "But doctor, I did not have a check-up!"

     For a moment the doctor looked puzzled. Then he said, "Oh, yes, it was the patient before you who had

a check-up. How absent-minded I am!"

1. The doctor took Edison's story for example ____.

A. to show absent-mindedness is common among people

B. because he liked telling stories

C. to make the author laugh

D. to make fun of Edison

2. The underlined word "absent-mindedness" in the second paragraph probably means ____.

A. a feeling of anger

B. a feeling of sadness

C. an emotion (情绪) of excitement

D. a trouble in which people often forget this or that

3. According to the passage, who was absent-minded?

A. Only the author.

B. The author's wife.

C. The doctor alone.

D. The author and the doctor.

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