题干

已知双缝到光屏之间的距离L=500mm,双缝之间的距离d=0.50mm,单缝到双缝的距离s=100mm,测量单色光的波长实验中,测得第1条亮条纹与第8条亮条纹的中心之间的距离为4.48mm,则相邻亮条纹之间的距离△x=____mm;入射光的波长λ=____m(结果保留两位有效数字).

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0.64,6.4×107

同类题1

阅读下面的文字,完成文后小题。

    前几年,我提出了“各美其美,美人之美,美美与共,天下大同”的设想,这是我的心愿。要想达到这样的境界并不容易。比如当今世界上许多发展中国家,历史上大多遭受过西方殖民主义的欺凌,这些国家的民众,由于受一种被扭曲的心理的影响,容易产生两种截然相反的倾向:一种是妄自菲薄,盲目崇拜西方;一种是闭关排外,甚至极端仇视西方。目前,这种仇视西方的状况似乎已经酝酿成一股社会潮流。从另一方面说,作为强势文明的发达国家,容易妄自尊大,热衷于搞“传教”,一股脑儿地推销自己的“文明”,其实这样做会蒙住自己的耳目,成了不了解世界大势的井底之蛙。在中国的历史上,也出现过“盲目崇拜”和“闭关排外”的现象。希望今天的中国学术界,能够彻底拋弃妄自菲薄、盲目崇拜西方或者妄自尊大、闭关排外的心理。

    中华文化经历了几千年,积聚了无数先人的聪明智慧和宝贵经验,我想我们今天尤其需要下大力气学习、研究和总结。面对今天这种“信息爆炸”、形形色色“异文化”纷至沓来的时代,我们需认真思考怎么办。全盘接受、盲目排斥都不是好的方法,我们应该用一种理智的、稳健的,不是轻率的、情绪化的心态来“欣赏”它。要知道,不论哪种文明,都不是完美无缺的,都有精华和糟粕,因此对涌进来的异文化我们既要“理解”,又要有所“选择”。

    为了人类能够生活在一个“和而不同”的世界上,从现在起就必须提倡在审美的、人文的层次上,在人们的社会活动中,树立起一个“美美与共”的文化心态,这是人们文化观念上的一场深刻大变革,它可能与当前世界上很多人习惯的思维模式和行为方式相抵触。在这场变革中,一定会因为不被理解而引起一些人的非议甚至抵制,特别是当触动到某些集团的利益的时候,可能还会受到猛烈的攻击。但是,当我们看到人类前进的步伐已经迈上全球化、信息化的道路;已经到了一个必须尽快解决全球化和人类不同文明如何相得益彰、共同繁荣的紧要关头,这些抵制和攻击又算得了什么。

(选自《美美与共和人类文明》费孝通,有删节)

同类题3

阅读理解

B

    “Mum, may Patti come over?” asked Meg.

    “Not until you clean your room,” replied Mum.

    Meg said on the phone unhappily, “I have to clean my room first.”

    At the other end, Patti laughed. She said to Meg, “That's funny. My mum just said I can't go anywhere until I clean my room.”

    After hanging up (挂断电话), the girls went to their own rooms. Each girl looked around at her mess. Slowly they started cleaning their rooms.

    Meg said to herself, “Maybe we could talk on the phone while we work. It would be hard to work and talk at the same time, though.”

    Patti thought, “Until I clean my room, I can't leave. Meg may leave, but she can't have anyone over.” Then Patti asked her mum, “Mum, may Meg come?” “Sure,” said Patti's mum. “Remember, you must have your room cleaned before leaving the house.”

    Patti ran to the phone and called Meg. “I've got an idea!” she told Meg.

    A few minutes later, Meg went over to Patti's house. Her mum allowed her to go because she promised to clean her room when she returned.

    While dancing, singing and talking, the girls worked. One hour later, the room became clean. It was fun! The room looked great. Patti's mum was happy. She called Meg's mum and told her everything. Meg's mum said Patti could come to help Meg.

    The girls quickly went to Meg's house. They worked and played until the room was clean. The girls learned that working together could make cleaning fun and easy!