如图所示，质量为M的铁箱内装有质量为m的货物．以某一初速度向上竖直抛出，上升的最

发布时间：2017-07-28 23:18 │ 来源：www.tikuol.com

题型：计算题

问题：

如图所示，质量为M的铁箱内装有质量为m的货物．以某一初速度向上竖直抛出，上升的最大高度为H，下落过程的加速度大小为a，重力加速度为g，铁箱运动过程受到的空气阻力大小不变．求：

（1）铁箱下落过程经历的时间；

（2）铁箱和货物在落地前的运动过程中克服空气阻力做的功；

（3）上升过程货物受到铁箱的作用力．

考点：功匀变速直线运动的位移与时间的关系牛顿运动定律的应用

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综合填空。根据短文大意，从方框内选择恰当的单词，将其正确形式填到横线上(每词限用一次)。

learn, be, for, high, about, children, late, carefully, better, animal

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Try to help others, try to think 5______ others, not only yourself.
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make life 6______ for everyone.
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(网页) that are good 10______ you. You can use the Internet for fun or homework.

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亿位是最高的数位，没有比它更高的数位了．______．

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有关制剂中易水解的药物有（）

A.酚类

B.酰胺类

C.烯醇类

D.六碳糖

E.芳胺类

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将酒度大于40°的酒，称之为高度酒。（）

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金属塑性加工外力可以分为：

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