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问题 选择题

对于做匀速圆周运动的物体，下列说法正确的是（　　）

A．物体处于平衡状态

B．物体所受的合外力为零

C．物体的线速度是不变的

D．物体转动的角速度不变

答案

A、匀速圆周运动所受合外力提供向心力，所以合外力不为零，不是平衡状态，故AB错误；

C、匀速圆周运动线速度的大小不变，方向时刻改变，故C错误；

D、匀速圆周运动的角速度不变，故D正确．

故选：D

听力题

根据句子意思，用括号中所给汉语提示或英语单词的适当形式填空。(每空一词)

小题1:The Five-pavilion Bridge is the        of the Slender West Lake.(象征)

小题2:He devoted his life to         the poor people’s living conditions. (改善)

小题3:My cousin’s          birthday is coming and I will buy him a present . (十九)

小题4:If you don’t go there, I won’t go        . (也)

小题5:We have a meeting on            afternoon.（星期三）

小题6:The boy has been used to         (watch) TV after finishing his homework .

小题7:The teacher told us that Yangzhou          (lie) on the northern side of the Yangtze River.

小题8:Titanic is a romantic film that is           (direct) by James Cameron.

小题9:       with winter, spring is much better in some ways.(compare)

小题10:The       disappearance of the Flight MH370 makes all the people worried. (suddenly)
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多项选择题

1725年，天津州升为“直隶州”，下辖（）三县。

A.武清

B.静海

C.青县
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