试题与答案

如图是某学习小组同学设计的研究“电磁铁磁性强弱”的实验电路图. (1)要判断电磁

题型:实验题

题目:

如图是某学习小组同学设计的研究“电磁铁磁性强弱”的实验电路图.

(1)要判断电磁铁的磁性强弱,可观察_____________来确定;要改变电流大小可以通过滑动变阻器滑片的滑动来实现 .

(2)表是该组同学所做实验的记录:

①比较实验____和_____可得出的结论是:线圈匝数不变,电流越大磁性越强.

②比较实验____和_____可得出的结论是:电流不变,线圈匝数越多磁性越强.

(3)在与同学们交流讨论时,另一组的一位同学提出一个问题:“当线圈中的电流和匝数一定时,电磁铁的磁性强弱会不会还与线圈内的铁芯大小有关?”现有大小不同的两根铁芯,利用本题电路说出你验证猜想的方法_____________________________________.

答案:

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题型:阅读理解

阅读理解。

     People say teenagers are no good. They make too much noise in shopping malls; they drive recklessly

up and down America's main streets; they carry chips on their shoulders as big as the Sears Tower. And

at least some of the time those things are true. But we shouldn't forget that there are hard moments in the

life of a teenager too.

     I watched such a moment not long ago at a woman's funeral. I didn't expect the event to affect me.

Through much of the ceremony, in fact, I remained unmoved.

     The teenage grandson stepped forward. With his very first deep breath, every heart in that church was achingly reminded of something we had all forgotten. Softly he began: "I want to share a few values that

Nana taught me. She never failed to see light in any situation. When our family dog would truly attack her, what would Nana say? 'oh, what beautiful barking that dog has!' That was Nana. "

     "She was a strong woman who often lived in the shadow of my grandpa, who was a successful

businessman in this city. But she was the one behind the scenes who provided the strength and support

for my grandpa's career," he said, with a voice now trembling, "That was Nana's way."

     Through a low sob, he continued, "Whenever she did anything worth recognition, you'd have to hear

about it from a different source, because she was never one to show off."

     Finally, in a voice breaking free of sorrow, he looked up and said, "Nana taught me courage. She put

up an incredible fight to the end, when she died peacefully, which is how she lived her life. That was

Nana's way, and I hope I can carry on in the same manner."

     There are no hearts as sensitive as those of teenagers, because everything is happening to them for the

first time. The trouble with teenagers is that they haven't learned to be controlled.

When that boy rose to speak about the woman who surely had been his truest and best friend, his honest

voice dragged each of us out into the open where we could no longer hide in the calm ceremony. He

exposed us to the truth about this very real woman who believed in a boy who probably tried the

patience of many adults. He reminded us that his grandmother was more than another dot on the chart of

life and death.

     All over again we felt those powerful losses crossing our own hearts, and we knew that when you say

good-bye to something happy, something young in yourself. And that something never really returns, and

the pain never really goes away.

1. In the first paragraph, the writer gave some examples to________ .

A. support his idea that young people are no good

B. introduce his point of view about young people

C. tell people every coin has its two sides

D. show young people often make mistakes

2. From the boy's speech, we know _______ .

A. his grandmother had great influence on him

B. they had a dog which often attacked people

C. people had forgotten her until the boy appeared

D. his grandmother was so weak that she is always living in the shadow of his grandpa

3. Which of the following statements is true?

A. The boy 's speech moved no one present at the funeral except the writer

B. The boy's being good at expressing himself enabled him to draw everyone's attention

C. The boy was too grieved to accept the fact that his grandmother had passed away

D. The writer didn't expect the event would affect him

4. What words can best describe grandmother's quality?

A. Weak, mild and modest

B. Easygoing, cautious and considerate

C. Sensitive and hard on others

D. Patient, optimistic, strong and helpful.

5. The passage tells the readers_______ .

A. facing certain bitter facts help young people to grow

B. young people have to control themselves

C. the adults should learn from the young

D. the adults should teach the young how to be brave    

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