从足够高处先后让两个钢球自由下落，两球间用长为9.8m的细绳连结。第一个球下落1

发布时间：2017-05-17 15:18 │ 来源：www.tikuol.com

题型：计算题

问题：

从足够高处先后让两个钢球自由下落，两球间用长为9.8m的细绳连结。第一个球下落1s后第二个球开始下落。不计空间阻力及绳的质量，试求在第二个球开始下落后多长的时间，连结两球的细绳刚好被拉直？（g取9.8m／s²）

考点：自由落体运动

题型：计算题

阅读下面5段语言材料，请找出与它们相对应的段落大意，并将其标号填入下列横线上。

1. Do you think you have a poor memory? The following
suggestions may help you improve. You may be able to get
better grades!
2. Be interested. Tell yourself that you want to learn what
you need to remember. If you keep thinking about how bad
your memory is, your brain will not be active. Think about
something hopeful.
3. Go over information often and "over-learn". Review
what you've learned the same day you learn it. Look back
on it from time to time. The more often you study the
information, the easier it will be for you to recall it.
4. If you're trying to understand something that's
especially difficult, try to get an overview; don't think too
much about the details. If you're able to explain it to
someone else in your own words, it shows you know it.
5. Do you stay up late? Do you take exercise? Good life
habits help your memory. Exercise brings you enough
oxygen (氧气) and makes your brain more active.

A. Having interest in what you learn.

B. Give you some suggestions.

C. Reviewing is very important.

D. Having a good life habit is helpful.

E. Understanding is necessary.

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题型：计算题

小军是个正常男孩，那么他的体细胞中染色体的组成是（）

A．22+XY

B．XX

C．44+XY

D．XY

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题型：计算题

1934年的某史书记载：“妇女装束益趣新奇。先是旗袍短才及膝，袖达肘际，赤露两臂；裤长仅尺余，下服高腰洋袜，两腿皆外露；首挽圆髻，不钗不冠，近则截发烙之（指烫发），使曲散垂耳际……足着高跟鞋，头戴斜顶小帽，除戒指、臂铡外，簪环皆废矣。”对此材料理解，错误的是 [ ]

A．社会生活受到西方文明的冲击

B．旗袍结合中西样式成为时尚

C．社会审美观念追随西方潮流

D．妇女追求个性解放成为普遍现象

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题型：计算题

A房地产开发公司（以下简称A公司）在取得允许的条件下，拟开发城市中心区的空地，规划用途为商住两用。A公司将该项目委托给专业能力较强的B房地产经纪公司（以下简称B公司）进行市场调查，经调查，B公司认为该地块适合开发商场。

若B公司在对所研究对象进行全面分析的基础上，选择少数有代表性的单位，进行深入周密的调查研究，以达到了解总体的特征和本质的方法属于（）。

A.重点调查

B.典型调查

C.抽样调查

D.全面调查

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题型：计算题

眉间尺和宴之敖（黑衣人）是哪部作品中的人物《（）》。

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