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甲升降机比乙升降机的机械效率高,它们分别把相同质量的物体匀速提升相同的高度。则
A.乙升降机提升重物做的有用功较多
B.甲升降机的电动机做的额外功较多
C.甲升降机的电动机做的总功较少
D.乙升降机的电动机做的总功较少

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如图所示,一把太阳伞固定在地面上,一阵大风吹来,伞面被“吸”,严重变形。下列有关这一现象及其解释,正确的是
A.伞面被向下“吸’’,伞上方的空气流速大于下方
B.伞面被向上“吸”,伞上方的空气流速大于下方
C.伞面被向下“吸”,伞上方的空气流速小于下方
D.伞面被向上“吸”,伞上方的空气流速小于下方

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下图表示四冲程内燃机工作时各冲程的示意图,它们正确的排列顺序为
A.甲、乙、丙、丁B.丁、丙、乙、甲
C.甲、丙、乙、丁D.甲、丁、乙、丙

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如图所示的电路中,R1、R2均为定值电阻,电源电压不变,闭合开关S1、S2,两电表均有示数。若断开开关S2,则
A.电流表的示数变大,电压表的示数变小
B.电流表的示数变小,电压表的示数变大
C.电流表和电压表的示数都变小
D.电流表和电压表的示数都变大

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科目: 来源: 题型:阅读理解

There was a boy who was sent by his parents to a boarding school (寄宿学校).   36   being sent away, this boy was the   37   student in his class. He was at the top in every   38   always with high marks.
But the boy changed after   39   home and attending the boarding school. His grades started   40  . He hated being in a   41  . He was lonely all the time. And there were especially dark times when he   42   committing suicide (自杀). All of this was because he felt   43   and no one loved him.
His parents started   44   about the boy. But they even did not know what was   45   with him. So his dad decided to travel to the boarding school and   46   him.
They sat on the bank of the lake near the school. The father started asking him some casual questions about his classes, teachers and   47  . After some time his dad said, “Do you know, son, why I am here today?”
The boy answered back, “To   48   my grades?”
“No, no,” his dad replied. “I am here to tell you that you are the most   49   person for me. I want to see you   50  . I don’t care about grades. I care about you. I care about your happiness. YOU ARE MY LIFE.”
These words   51   the boy’s eyes to be filled with tears. He   52   his dad. They didn’t say anything to each other for a long time.
Now the boy had   53   he wanted. He knew there was someone on this earth who cared for him deeply. He   54   the world to someone. And today this young man is in college at the top of his class and no one has ever seen him   55  !
【小题1】
A.AfterB.BeforeC.WhenD.While
【小题2】
A.hardestB.naughtiestC.brightestD.dullest
【小题3】
A.examB.activityC.gameD.class
【小题4】
A.comingB.returningC.leavingD.reaching
【小题5】
A.risingB.increasingC.reducingD.dropping
【小题6】
A.groupB.termC.company D.party
【小题7】
A.led toB.felt likeC.thought backD.looked for
【小题8】
A.worthless B.carelessC.concernedD.annoyed
【小题9】
A.caringB.turningC.worryingD.speaking
【小题10】
A.crazyB.trueC.possibleD.wrong
【小题11】
A.talk withB.listen toC.tell toD.care about
【小题12】
A.familyB.friendsC.studyD.grades
【小题13】
A.realizeB.analyzeC.checkD.test
【小题14】
A.outstandingB.importantC.famousD.familiar
【小题15】
A.happyB.excellentC.interestedD.satisfied
【小题16】
A.causedB.wantedC.encouragedD.forced
【小题17】
A.answeredB.ignoredC.hatedD.hugged
【小题18】
A.nothingB.somethingC.everythingD.anything
【小题19】
A.showedB.meant C.intendedD.expressed
【小题20】
A.sadB.angryC.pleasantD.joyful

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对下列四幅图阐述合理的是
A.A图:磁场能产生电流
B.B图:闭合开关,通电导体在磁场中受到力
C.C图:闭合开关,导体棒在磁场中受到力
D.D图:微波炉利用电流的热效应工作

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2009年10月,国际航空节在莱芜雪野旅游区举行,期间进行了轻型飞机特技飞行、热气球、动力悬挂滑翔伞等8个大项21个小项的精彩比赛和表演。在热气球表演中:有一热气球正在加速上升,在其加速上升的过程中,它受到的浮力_______重力(选填“大于”、“等于”或“小于”),它的重力势能_______ (选填“变大”、“变小”或“不变”)。

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随着科技的发展,过去“呼风唤雨”的神话已成为现实。人工降雨是用飞机在空中喷洒干冰(固态二氧化碳),干冰在空气中迅速吸热_______,使空气温度急剧下降,空气中的水蒸气遇冷_______成小冰粒,冰粒逐渐变大而下落,下落过程中熔化成水滴,水滴降落就形成了雨。(填物态变化的名称)

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世博会开幕式上,演员们在放声歌唱,有多种乐器同时为他们伴奏,观众依据听到伴奏声的_______能判断出是哪种乐器在演奏。他们的声音听起来有丰富的立体感,这主要是由于人的听觉具有_______效应。

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2010年4月14日7时49分40秒,青海省玉树藏族自治州玉树县发生7.1级地震,搜救工作中遇到了很多困难。灾区处于高原地区,海拔高,很多救援队员在救援时出现了不同程度的高原反应,搜索犬的搜索效率、效能也受到了不同程度的影响。产生高原反应的其中一个原因就是气压随高度的增加而_______ (选填“增大”或“减小”)。救援时,救援人员能用撬棒撬起一块较大的石头,这是利用了_______原理。

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