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题目列表(包括答案和解析)

如图19所示,2012年的“财富”的象征――有车有房有切糕!切糕密度较大,一小块都很沉,卖价以两(1两=50g)为单位,致使很多人莫名上当受骗。为了测量切糕的密度,小明进行了如下的实验操作:

A.把托盘天平放在水平桌面上;

B.按照如图20所示,调节天平在水平位置平衡;

C.将切糕用极薄的保鲜膜包好,再用细线系好后慢慢地放入量筒中,并记下水和切糕的总体积;

D.在量筒中倒入适量的水,并记下水的体积;

E.在天平左右盘各垫上同样大小的纸片,将切糕放在左盘中,在右盘中增减砝码并移动游码直至横梁在水平位置平衡。

如图20,请你帮助小明回答下面五个问题:

(1)如图甲所示,小明在使用天平过程中的错误是:           

(2)改正错误后,正确的实验操作顺序是:A、B            

(3)在称量过程中,发现分度盘的指针如图乙所示,此时应将游码向___________________ (选填“左”或“右”)端调。

(4)正确称量时,天平平衡时右盘中的砝码质量、游码在标尺上的位置如图丙所示,切糕的质量为__________g;用量筒测量切糕的体积如图丁所示,则切糕的密度是   kg/m3。到此,明白了小切糕,大质量,花钱多的秘密了。

(5)由于切糕具有吸水性,为了防止其吸水,小明使用了该方案。本次实验测出的密度值比真实值偏大______(选填“偏大”或“偏小”)

车次

站名

到达时间

开车时间

里程

G81

北京西

始发站

13:05

0

G81

石家庄

14:24

14:27

281

G81

郑州东

16:17

16:20

693

G81

驻马店西

17:05

17:08

912

G81

武汉

18:12

18:17

1229

G81

衡山西

20:15

20:20

1727

G81

广州

22:32

终点站

2298

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完形填空 (共20小题;每小题1分,满分20分)
请认真阅读下面短文,从短文后各题所给的A、B、C、D四个选项中,选出最佳选项,并在答题卡上将该项涂黑。
Certainly dustmen prefer to be known as "Reuse Collection and Disposal Officers". You may think that this is rather    36 , and it is better to call a spade a spade. But dustmen can be as    37  as people of any other occupation, though we must     38   that their job is not a    39    one in the world. We often take dustmen for granted. Perhaps because they usually come very early in the morning, before most people are     40   .We are likely to forget their     41   .Our dustbins are    42   regularly, but we    43    stop to think about the men who do this. However, it is one of the most important jobs in the world, and when there are no dustmen to    44   the rubbish, the general    45   soon becomes aware that something is wrong. Recently, the dustmen of England went on strike for higher wages.
During the first few days it was regarded as a    46  .But when the first two weeks had passed, and the dustbins were overflowing in nearly every backyard in the country, the joke did not seem so    47   any more.    48   the strike continued, people could not    49   the hills of rubbish around their dustbins, and they looked for other places in which to    50  it. Even Leicester Square, in the heart of West End of London, was    51   high with plastic bags full of smelly rubbish. This was a(n)    52   attraction that the people of London were not at all     53   to see. Even when the strike was over, it took several weeks for the country to get cleaned up completely. Perhaps now the English people appreciate the work of    54  dustmen rather more    55   and won't take them for granted any more.
【小题1】
A.cleverB.sillyC.interestingD.reasonable
【小题2】
A.sensitiveB.carelessC.hopefulD.shy
【小题3】
A.realizeB.believeC.knowD.admit
【小题4】
A.necessaryB.difficultC.romanticD.heavy
【小题5】
A.awayB.upC.downD.in
【小题6】.
A.existenceB.presenceC.absenceD.performance
【小题7】
A.cleanedB.filledC.emptiedD.burned
【小题8】
A.generallyB.frequentlyC.sometimesD.seldom
【小题9】
A.take awayB.take offC.take upD.take on
【小题10】
A.societyB.citizenC.publicD.community
【小题11】
A.trickB.jokeC.troubleD.show
【小题12】
A.pleasingB.excitedC.stupidD.funny
【小题13】
A.WhenB.WhileC.AsD.Because
【小题14】
A.bearB.containC.manageD.control
【小题15】
A.keep offB.give upC.take care ofD.get rid of
【小题16】
A.crowdedB.piledC.fixedD.put
【小题17】
A.businessB.industrialC.touristD.agricultural
【小题18】.
A.disappointedB.seriousC.nervousD.happy
【小题19】
A.itsB.herC.hisD.their
【小题20】
A.highlyB.eagerlyC.lowlyD.entirely

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按下例要求完成作图

(1)在图17中画出排球所受重力的示意图

(2)如图18所示,凸透镜的焦距为1.5cm,O为透镜的光心。请按照实际尺寸标出凸透镜右侧焦点F的位置,并画出入射光线所对应的折射光线。

(3)在A点作用一个力F,使图19中所示的杠杆保持静止。力F的方向不同,则力F大小也不同。当力F最小时,请画出这时力F的示意图

(4)请将如图20所示电路元件,连接成符合安全用电要求的电路图。

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物理学的每一次重大发现,都极大地推动了科学和技术的进步.
①17~18世纪,力学和热学的发展,促进了蒸汽机的研制和改进,使人类社会进入“蒸汽时代”;
②19世纪,电磁学研究的巨大成就,人们成功地制造了各种电气设备,使人类社会由“蒸汽时代”进入“电气时代”;
③20世纪以来,电子计算机的普及,互联网等各种现代信息技术的不断完善,使人类社会进行“电子信息时代”.
上列有关论述都正确的是(  )
A、①②B、②③C、①③D、①②③

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物理学的每一次重大发现,都极大地推动了科学和技术的进步.
①17~18世纪,力学和热学的发展,促进了蒸汽机的研制和改进,使人类社会进入“蒸汽时代”;
②19世纪,电磁学研究的巨大成就,人们成功地制造了各种电气设备,使人类社会由“蒸汽时代”进入“电气时代”;
③20世纪以来,电子计算机的普及,互联网等各种现代信息技术的不断完善,使人类社会进行“电子信息时代”.
上列有关论述都正确的是(  )
A.①②B.②③C.①③D.①②③

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