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问题 单项选择题

水平简支梁如图所示，不计杆自重，如外力P1与P2相互平行且铅垂，又P1=P2=P，则支座A的反力RA为( )。

答案

参考答案：D

解析： 因为P1、P2大小相等，方向相反，但不在一直线上，故形成力偶Ph，力偶只能与力偶平衡，因此支座A处反力必须与链杆B平行且向下，即
RA×[*]l＝Ph，所以RA＝[*]

听力题

根据下列句子及所给单词的首字母，写出各单词的完全形式（每空限填一词）

小题1:I hear that their class c__________ of 26 boys and 14 girls.

小题2:What she said was so c__________ that I fully believed her.

小题3:To our d__________, we are going to have a very long winter vacation.

小题4:The man acted rudely and thus made a bad i__________ on us.

小题5:My father is so s__________ that no one can make him change his decision.

小题6:A great many houses were d__________ in the earthquake and many people became homeless.

小题7:U__________ my sister who is fond of pop music, I like classical music.

小题8:We can draw a c__________ from the above discussion.

小题9:With many pictures, this book is i__________ for the children under 6 years old.

小题10:When a_________ the house, they found something unusual, so they stopped to have a look.
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判断题

三面图的投影关系：正面图和侧面图长对正。( )
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