题干

光电鼠标在电脑中应用非常广泛,其原理就是利用光源照射鼠标垫表面(如图所示),并被反射回光学感应器(相当于光屏),当鼠标移动时,感应器会连续接收鼠标垫表面所成的像,并利用数字信号来处理比较各个影像,以确定移动的距离和方向。产生的结果传回计算机,而屏幕上的光标会根据这些结果来移动。图中光学感应器、透镜、光源等元件固定在鼠标内,当光源的光照射在粗糙的鼠标垫上时会发生____反射;当鼠标平放在鼠标垫上,凸透镜到鼠标垫的距离为7mm,光学感应器距凸透镜3mm,则在光学感应器上成____像。

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同类题2

阅读材料,同答下列问题。

材料一:2016年9月2日《人民日报》载文指出,中华文明是世界诸多文明中唯一没有中断过的文明。在5000多年历史中孕育发展的中华文化,是中华民族的根和魂。

    春秋战国时期,中华大地上产生了诸子百家,儒家重“人道”,道家重“天道”,二者相互补充、相得益彰,形成了中华文化的基本价值取向。墨家则建立了严谨的逻辑体系,并将其应用于自然科学,对时空、光学、力学、几何学等方面的问题,是诸子百家中大放异彩的一朵奇葩。

    以诸子百家为重要代表的中华文化显示出强劲生命力,始终以开放姿态吸取各种养分,在会通的基础上消化吸收各家理论,形成了一条独特的自我创新之路。

材料二:腾讯公司董事会主席首席执行官马化腾认为,老百姓借助社交平台可以活化传统文化,比如过年发红包是特色民俗,微信的介入就点燃了大家的热情。植根传统,传承文化,技术创新可为传统文化的发展提供手段,如动画电影《大鱼海棠》的灵感来源于《庄子·逍遥游》,讲述了一个掌管海棠花的少女与人类男孩的灵魂“鲲”的奇幻故事;《百鸟朝凤》讲述了唢呐艺人的坚守;《白鹿原》《归来》则讲述时代变迁。中华文化与新的电影语言深度结合,传统文化、当代文化、红色文化随中国电影的内容拓展,不断突破绽放。以影载文、扬帆出海,文化的价值表现在走出去展示魅力的自信里,还表现在有海纳百川、熔铸百家的气魄中,文化在交流、借鉴与融合中发展。

材料三:哈佛大学一项调查显示:爱做家务的孩子和不爱做家务的孩子成年之后的就业率为15:1,犯罪率为l:10,同时,爱做家务的孩子心理疾病患病率也较低。

    在我国,勤劳是中华民族的传统美德,培养人的劳动能力是各级各类教育的职责所在,近年来,劳动教育被淡化、虚化和边缘化。在学校“德智体美劳”全面发展中,“劳”已成为素质教育的短板,国家教育部2016年9月发布的《中国学生发展核心素养》将劳动意识置于实践创新素养的首要方面,重点要求:尊重劳动,具有积极的劳动态度和良好的劳动习惯;在主动参加的家务劳动、生产劳动、公益活动和社会实践中,提高劳动意识等。

同类题3

通读下面短文, 掌握其大意, 然后在每小题所给的四个选项中, 选出一个最佳答案, 并将答题卡上对应的选项涂黑。

    My parents are busy with their work every day. You can't see there is love 1 them. They don't act in the romantic(浪漫的)2that I read in books or I see on TV.

    One day, while Mom was sewing(缝) a quilt,I 3 beside her. “Mom, I have a question,” I said after a while.

    “What?” she asked.

    “Is there love between you and Dad?” I asked her in a very low voice.

    She stopped sewing and 4 her head. Then she bowed her head and went on sewing.

    I thought I had hurt her. At last I heard my mother say, “Susan, look at this thread(线). Sometimes it appears, but most of it disappears in the quilt. It makes the quilt5. If life is a quilt, then love should be a thread. It can hardly be seen, but it's 6 there.”

    I couldn't understand her 7 the next spring. My father suddenly got sick. Mom had to stay with him in the hospital for a month.

    After they 8, my mother helped my father walk slowly down the country road every day. My father had never been so gentle.

    “Dad, how are you 9 now?” I asked him one day. “Susan, don't worry about me,” he said. “I just like walking with your Mom.”

     Once I thought 10 meant flowers, gifts and sweet kisses. But from this experience, I understand that it is just a thread in the quilt of our life . It is inside, making life strong and warm.