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问题 实验题

在“探究有哪些因素影响滑轮组的机械效率”的实验中，某小组利用图所示装置测得了四组数据，如下表所示。

（1）前三次实验中，第_______次实验数据明显出现错误，应当剔除。

（2）第四次实验中，有用功是__________J，总功是___________J，滑轮组的机械效率为_____________。

（3）根据以上信息，请判断：该小组设计这四次实验的目的是为了探究滑轮组的机械效率与_____________________________是否有关。

答案

（1）3   （2）0.3    0.36   83.3%     （3）钩码上升的高度

（1）前三次实验中，第3次实验数据明显出现错误，应当剔除

（2）第四次实验中，有用功是Gh=3×0.1=0.3J，总功是Fs=1.2×0.3=0.36J，滑轮组的机械效率为％

（3）根据以上信息，该小组设计这四次实验的目的是为了探究滑轮组的机械效率与钩码上升的高度是否有关

阅读理解

Mobile phone has become a problem for high schools. Some high-school students in Australia are not allowed to carry mobile phones during school hours.

Mobile phone used among children has become a problem for the school years. Several children have got mobile phones as Christmas presents, and more students will want them. .

Marry Brown, a headmaster, said that mobile phone was a distraction(分心事) to students during school hours and it also gave teachers so much trouble in their classrooms. Teachers were also saying that sometimes students might use phone messages to cheat during exams .

She said some schools had tried to ban(禁止) mobile phones. Some parents felt unhappy because they couldn’t get in touch with their children.

Many teachers said students should not have mobile phones at school. But there was a good reason that they could leave their phones at school offices. They also said they were easily lost and were a distraction for studies.

Many people say that they understand why parents would want their children to  have phones, but they think schools should let the students know when they can use their mobile phones.

小题1:Some high schools in Australia have stopped students from carrying mobile phones         

A．because they are students

B．when they are free

C．when they are at school

D．because they are children小题2:What does the word “cheat” mean in Chinese in this passage?

A．聊天

B．核对

C．查询

D．作弊小题3:Some children get mobile phones from          as presents.

A．the makers and sellers

B．the passers-by and strangers

C．their parents and friends

D．some mobile phone user小题4:Some parents felt unhappy because they couldn’t         during school hours.

A．use their mobile phones

B．leave their mobile phones in the school office

C．help the teachers with their work

D．get in touch with their children小题5:The passage tells us that       .

A．students shouldn’t have mobile phones at school except for special reasons

B．it is important to ban students from using mobile phones at school

C．some parents felt unhappy because they couldn’t use their phones at home

D．parents should teach their children how to use mobile phones during school hours
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问答题 案例分析题

某安装工程公司承接架空蒸汽管道工程。管道工程由型钢支架工程和管道安装组成。

项目部根据现场实测数据，结合工程所在地的人工、材料、机械台班价格编制了每10t型钢支架工程的直接工程费单价，经工程所在地综合人工日工资标准测算，每吨型钢支架人工费为1380元，每吨型钢支架工程用各种型钢1.1t，每吨型钢材料平均单价5600元，其他材料费380元，各种机械台班费400元。

由于管线需用钢管量大，项目部编制了两套管线施工方案。两套方案的计划人工费15万元，计划用钢材500t，计划价格为7000元/t。甲方案为买现货，价格为6900元/t，乙方案为15天后供货，价格为6700元/t。如按乙方案实行，人工费需增加6000元，机械台班费需增加1.5万元，现场管理费需增加1万元，通过进度分析，甲、乙两方案均不影响工期。

工程进行过程中，发生了以下事件：

事件一：在采购一批管道焊接用的共2t低合金耐热钢焊条时，施工单位按建设单位指定的合格供应商确定了焊材供应商。施工单位对供应商首次送货的0.5t焊条进行抽样检测合格。对后两次送货的其余1.5t焊条均未检测，接收后直接用于焊接。在施焊过程中发现焊缝出现大量延迟裂纹。建设单位与监理工程师对焊条重新进行抽样检测，确认为不合格。为之建设单位要求施工单位承担全部责任，所有用此供应商的焊条进行焊接的管线全部重新组焊。施工单位认为供应商是建设单位指定的，应由建设单位承担责任。

事件二：安装工程公司项目部在工程施工自检时，发现架空蒸气管道坡度、排水装置、放气装置、疏水器安装均不符合规范要求。检查组要求项目部立即整改纠正，采取措施，确保质量、安全、成本目标，按期完成任务。

事件三：建设单位在工程后期组织进行工程质量大检查，对施工单位的一项通过检查验收合格的隐蔽工程进行重新检验，发现不符合质量验收标准。建设单位要求施工单位返工并支付检验费用。

事件二中，安装应达到规范的什么要求？
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