如图所示,在倾角为30°、静止的光滑斜面上,一辆在外力作用下加速下滑的小车上悬吊

题型:选择题

问题:

如图所示,在倾角为30°、静止的光滑斜面上,一辆在外力作用下加速下滑的小车上悬吊单摆的摆线总处于水平位置。已知车的质量和摆球的质量均为m,下列正确的是(    )

A.小车加速度为g/2

B.摆线中张力大小一定为mg

C.小车加速度为2g

D.摆线中张力大小一定 为2mg

考点:牛顿运动定律的应用
题型:选择题

阅读短文,然后用短文括号中所给词的适当形式填空。

     Climbing the highest mountains in the world is not an     1     (easily) job. You have to fight bad weather,

illness and fear. But Jordan Romero, a thirteen-year-old boy from America, will climb     2     (Asia) highest

mountain, Mount Qomolangma. He will set out this month.     3     (He) parents and helpers will climb with

him. He plans to take     4     (second) months for his climb. "I'm ready. But if I don't reach the top     5    

(successful), I'll try next time," he said. Jordan has already climbed the highest mountains of six other continents

(洲). If he     6     (get) to the top this time, he will become the youngest person to climb the world's highest

mountain.

1.                 2.                 3.                 4.                 5.                 6.             

题型:选择题

患者月经周期延后,经量减少渐至月经停闭,五心烦热,颧红唇干,骨蒸劳热,咳嗽唾血;舌红,少苔,脉细数。其治法是()

A.养血活血通经

B.补肾益气调经

C.燥湿化痰健脾

D.益气养血调经

E.养阴清热调经

题型:选择题

从业人员的自我制约是制约()。

A.自身行为

B.对客行为

C.礼节礼貌

D.主宾关系

题型:选择题

驾驶机动车遇到这种特殊情况怎样行驶?()

A.靠左侧减速让行

B.靠右侧减速让行

C.加速靠左侧让行

D.保持原行驶路线

题型:选择题

下列不属于合同特征的是( )。

A.合同是一种民事法律行为

B.合同以设立、变更、终止民事权利和义务关系为目的

C.合同是多方民事法律行为

D.合同是有偿的

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