如图所示，小球m自A点沿AD方向以初速度v逐渐接近固定在D点的小球n。已知AB弧

发布时间：2017-04-16 22:26 │ 来源：www.tikuol.com

题型：计算题

问题：

如图所示，小球m自A点沿AD方向以初速度v逐渐接近固定在D点的小球n。已知AB弧长为0.4m，AB圆弧半径R=10m，AD=10m，A、B、C、D在同一水平面上，则v为多大时，才能使m恰好碰到小球n？（g取10N/kg）

考点：简谐运动的周期、频率和角频率

题型：计算题

有资料表明：某地区高度每增加100 米，气温降低0.8 ℃，小明和小红想出一个测量山峰高度的办法，小红在山脚，小明在山顶，他们同时在上午9 时测得山脚温度是2.6 ℃，山顶温度是－2.2 ℃. 你知道山峰的高度吗？

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题型：计算题

完形填空。

history, choose, common, buy, make, enjoy, way, another, while, serve

     American summers are filled with outdoor picnics, baseball games and swimming pools. Summer
in America is a time 1_______ the outdoors, no matter how hot it might be. Let's take a look at some of the
popular drinks.
     Lemonade is 2_______ of all American summer drinks. It 3_______ by mixing lemon juice, water and sugar.
It is usually served very cold, with ice. Ice tea is 4_______ popular summer drink in America. Ice tea is usually
5_______ in a tall glass of ice. Many Americans 6_______ to add sugar to sweeten the drink. This drink is often
drunk in the afternoon 7_______ relaxing in the shade.
     Ice tea is now also sold by the bottle, at almost any store in America.
     The Slurpee, a famous American drink in recent years, is a great 8_______ to cool off in the summer heat. It
is a mix of ice, sugar and fruit juices. However, the drink is mostly made of ice. They can 9_______ at most
small convenient stores. Slurpees are popular with young Americans.
     Milkshakes have a long 10_______ in America. It is made of a mix of ice cream, milk and flavoring.

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题型：计算题

下图为某人体内几种类型的细胞模式图。下列相关叙述中，不正确的是

A．这些细胞最初来源于同一个受精卵细胞

B．a的结构已发生很大变化，但仍属于真核细胞

C．这些细胞在结构上具有统一性

D．这些细胞在功能上是相似的

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题型：计算题

荷兰人设计制造的商船之所以成本低建造快，是因为其（）

A.大甲板、小舱容、无武器

B.小甲板、大舱容、无武器

C.小甲板、小舱容、无武器

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题型：计算题

双上肢周围性瘫痪，双下肢中枢性瘫痪，病变部位是（）

A.胸髓

B.内囊

C.大脑皮层

D.颈膨大

E.脑干

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