２０１０年２月１６日，在加拿大温哥华太平洋体育馆里举行的冬奥_爱下问搜题

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问题计算题

２０１０年２月１６日，在加拿大温哥华太平洋体育馆里举行的冬奥会花样滑冰双人滑项目自由滑的决赛中，最后一对出场的黑龙江籍选手申雪/赵宏博发挥出色夺得冠军，在退役之前终于成就了自己的梦想，实现花样滑冰双人滑大满贯．如图所示，赵宏博以自己为转动轴拉着申雪做匀速圆周运动，若赵宏博的转速为30 r/min，申雪触地冰鞋的线速度为4.7 m/s.求：

（1）申雪做圆周运动的角速度；

（2）申雪触地冰鞋做圆周运动的半径；

（3）若他们手拉手绕他们连线上的某点做同周期的匀速圆周运动，已知男、女运动员已知M_甲＝80 kg，M_乙＝40 kg，两人相距0.9 m，，求男、女运动员做圆周运动的半径分别为多少？

答案

（1）ω=π rad/s.（2）r="1.5" m.（3）R_男=0.3m，R_女=0.6m

题目分析：（1）n="30" r/min="0.5" r/s，

角速度ω=2πn=π rad/s.

（2）触地冰鞋做圆周运动的半径为r，

v=ωr，r== m="1.5" m.

（3）R_男=0.3m，R_女=0.6m

点评：掌握线速度和角速度的定义和关系。

完形填空

As Christmas is coming, there are presents to be bought, cards to be sent, and rooms to be cleaned. Parents are ___36___ with difficult jobs of hiding presents from curious young children. If the gifts are large, this is sometimes a real ___37___. On Christmas Eve, young children find the excitement almost unbearable. They are torn between the wish to go to bed early so that Father Christmas will bring their presents quickly and the wish to ___38___ up late so that they will not ___39____ the fun. The wish for gifts usually proves stronger. But though children go to bed early, they often lie ___40___ for a long time, hoping to get a short ___41___ at Father Christmas.
Last Christmas, my wife and I ___42___ hid a few large presents in the storeroom. I ___43___ the moment when my son, Jimmy, would ___44___ me where that new bike had come from, but ___45___ he did not see it.
On Christmas Eve, ___46___ took the children hours to go to sleep. It must have been nearly___47___ when my wife and I went quietly into their room and began ___48___ stockings. Then I pushed in the ___49____ I bought for Jimmy and left it beside the Christmas tree. We knew we would not get much sleep that night, for the children were ___50___ to get up early. At about five o’clock the next morning, we were ___51___ by loud sounds coming from the children’s room — they were shouting excitedly! ___52_____ I had time to get out of bed, young Jimmy came riding into the room on his new bike, and his sister, Mary, followed close behind pushing her new baby carriage. ____53_____ the baby arrived. He moved ___54____ the hands and knees into the room dragging a large balloon behind him. Suddenly it burst. That woke us up ___55___. The day had really begun with a band(巨响) !

D．successfully

D．fortunately

单项选择题 A1型题

生殖道沙眼衣原体感染治疗的有效药物是（）

A.头孢曲松

B.大观霉素

C.环孢素

D.阿奇霉素

E.制霉菌素