(单选题)29: 光滑支持面对物体的约束力作用与接触点,其方向沿接触面的公法线( ) A: 指向受力物体,为压力; B: 指向受力物体,为拉力; C: 背离受力物体,为压力; D: 背离受力物体,为拉力。 ...
(单选题)23: 下列说法不正确的是: A: 平面汇交力系的合力对平面内任一点的力矩等于力系中各力对同一点的力矩的代数和 B: 力偶不能与一个力等效也不能与一个力平衡; C: 力使物体绕矩心逆时针旋转为负; D: 力偶对其作用平面内任一点的矩恒等于力偶矩,而...
(单选题)17: 对于某一物体起限制作用的周围( ),称为约束。 A: 其他的力; B: 其他的物体; C: 其他的材料; D: 其他的力系。 ...
(单选题)11: 通常规定,物体( )转向时,力偶矩与力矩为负,反之为正。 A: 向右; B: 向左; C: 顺时针; D: 逆时针。 ...
(单选题)5: 铸铁试件轴向拉伸破坏是( ) A: 沿横截面拉断; B: 沿45°斜截面拉断; C: 沿横截面剪断; D: 沿45°斜截面剪断。 ...
(单选题)49: Shall we have another cup of tea? A: Do you like tea? B: Why not? C: Good tea. D: I'm thirsty. ...
(单选题)43: — Now let’s move on to another topic. Can you follow me? — ____________________, Professor. A: No, I am not. B: Yes, I will. C: No, I haven’t. D: Yes, perfectly. ...
(单选题)37: –I’m planning to study abroad and I want your advice. --____________. A: You do not have to. B: You ask me? C: What can I do for you? D: It is unnecessary. ...
(单选题)31: — Could I ask you a rather personal question? — Of course, ____________________. A: good idea B: that’s right C: that’s right D: go ahead ...
(单选题)25: On Monday mornings it usually ________ me an hour to drive to work although the actual distance is only 20 miles. A: takes B: is taking C: took D: will take ...