问题 选择题

在同一高度,把三个完全相同的小球以相同大小的速度同时抛出去,它们分做竖直上抛、竖直下抛和平抛运动,则下列说法正确的是(  )

A.每一时刻三个小球的速度均相等

B.落地时三个小球的速度相同

C.落地时三个小球的动能相同

D.三个小球在空中飞行的时间相同

答案

A、根据动能定理得,mgh=

1
2
mv2-
1
2
mv02知,重力做功相等,则落地时三个小球的动能相等,平抛运动和竖直上抛和竖直下抛运动的速度方向不同,则三个小球的速度不同.任一时刻小球下落的高度不同,根据动能定理小球的速度不等.故A、B错误,C正确.

D、平抛运动在竖直方向上做自由落体运动,在同一高度自由落体运动的时间小于竖直上抛运动的时间,大于竖直下抛运动的时间.故D错误.

故选C.

完形填空

阅读下面短文,简要回答问题。

Baloney is a kind of sausage that many Americans eat often. The word also has another meaning in English. It is used to describe something—usually something someone says—that is false or wrong or foolish.

Baloney sausage comes from the name of the Italian city, Bologna. The city is famous for its sausage, a mixture of smoked, spiced meat from cows and pigs. But, boloney sausage does not taste the same as beef or pork alone.

Some language experts think this different taste is responsible for the birth of the expression baloney. Baloney is an idea or statement that is nothing like the truth...in the same way that baloney sausage tastes nothing like the meat that is used to make it.

Baloney is a word often used by politicians to describe the ideas of their opponents.

The expression has been used for years. Fifty years ago, a former governor of New York State, Alfred Smith, criticized some claims by President Franklin Roosevelt about the successes of the Roosevelt administration. Smith said, “No matter how thin you slice it, it is still baloney.”

A similar word has almost the same meaning as baloney. It even sounds almost the same. The word is blarney. It began in Ireland about 1600.

The lord of Blarney castle, near Cork, agreed to surrender the castle to British troops. But he kept making excuses for postponing the surrender. And, he made them sound like very good excuses, “this is just more of the same blarney.”

The Irish castle now is famous for its Blarney stone. Kissing the stone is thought to give a person special powers of speech. One who has kissed the Blarney stone, so the story goes, can speak words of praise so smoothly and sweetly that you believe them, even when you know they are false.

73.小题1:Find in the passage a word closest in meaning to the underlined word “baloney”.

                                                                  

74.小题2:According to Americans, what does baloney refer to? (回答词数不超过8个)

                                                                  

75.小题3:What do you know about the lord of Blarney castle, near Cork?  (回答词数不超过6个)

                                                                  

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