(1)下列关于光具有波粒二象性的叙述中正确的是 ( ) A.光的波动性与机械波、

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问题:

(1)下列关于光具有波粒二象性的叙述中正确的是                    (  )

A.光的波动性与机械波、光的粒子性与质点都是等同的

B.大量光子产生的效果往往显示出波动性,个别光子产生的效果往往显示出

粒子性

C.光有波动性又有粒子性,是互相矛盾的,是不能统一的

D.光的频率越高,波动性越显著(2)试通过分析比较,具有相同动能的中子和电子的物质波波长的大小.

考点:光的偏振
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Dear Reader,

Think about an 11-year-old child spending her days washing clothes, looking after a baby brother, and doing hard work on the farm.

Think about a little girl. She knows there will not be enough food for dinner, and has no water to drink because it is not clean. She has watched her father, brother and sister lose their lives as the family has no money to send for a doctor.

Hard to believe? For Maria Pastora, these are the facts of life.

Maria would gladly walk to school, but her mother, now alone, really needs her at home. Maria had to leave school to work for her poor family.

But for five dollars a week, you can help out a child like Maria. Show her that somewhere, some­one will help her. Through Save the Children, you can help Maria’s mother get better crops (收成) from their farm, and earn the money to buy clothes and things for school.

To help Maria most, your money is to put to­gether with other helpers, so hardworking people can help themselves. Build a school or a hospital, make their farm better, bring in clean water... This is what Save the Children has been about since 1932.

For you there are many returns. You can write letters to each other, get photos, or study reports. Know you are helping and saving another person in the same world as you. That’s how Save the Chil­dren works. But without you, it can’t work. Please take a moment to fill in this form to help a child like Maria and her village.

It can make such a difference in her life and yours.

Save the Children

David L. Guyer

Chairman

(    ) 7. Maria’s father, brother and sister died because they_________.

A. were too poor to see a doctor   B. didn’t know where to find a doctor

C. didn’t have enough food to eat  D. were too busy to see a doctor

(    ) 8. This letter mainly tells you to_________.

A. know about poor people   B. earn some money for poor children

C. show pity to poor people   D. donate money to help poor children

(    ) 9. If you try to help a child like Maria, which of the following can’t you get from her?

A. You can often get some pictures from her.

B. You can get more money from her when she grows up.

C. You can often get her letters.

D. You can often be told how she is getting on.

(    ) 10. This letter most probably appears_________.

A. on TV     B. in a magazine     C. in a dictionary    D. on the radio

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古人云:“竭泽而渔,非不得鱼,明年无鱼;焚林而畋,非不收兽,明年无兽。”上述材料所蕴涵的哲学道理是 (  )

A.规律是事物运动过程中的联系

B.规律的存在和发生作用是无条件的

C.规律是可以被认识和改造的

D.违背规律必然要受到规律的惩罚

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除以一个不为零的数,等于乘以这个数的倒数.______.

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属于江苏名点小吃之一的是()。

A.叉烧包

B.担担面

C.淮扬汤包

D.一品烧饼

题型:计算题

齿轮(蜗轮)换向器最大变换方向为()度。

A.30

B.60

C.90

D.135

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