【单选题】We grease the bearings of all pumps at intervals.我们定期给所有泵的轴承加牛油 01010038
A.
We grease the bearings of some pumps periodically.
B.
We grease the bearings of several pumps periodically.
C.
We grease the bearings of only one pump periodically.
D.
The bearings of all pumps are greased periodically.
【单选题】The crankpin bearings are made of ( )
【单选题】The highest loads applied to the diesel engine crankshaft main bearings are ___________.
【判断题】力的可传性原理只适用于刚体,而不适用于变形体。
【简答题】Radial bearings are designed to pr movement of the rotating shaft; axial bearings, often called thrust bearings, are designed to pr movement of the shaft.
【单选题】下列说法错误的是( )
A.
刚体受三个力作用而平衡时,此三力作用线共面且汇交于一点
C.
作用力与反作用力总是大小相等、方向相反、作用线相同。
【单选题】在Windows 7操作系统中,不能用于退出应用程序的方法是______。
【判断题】Guide
bearings support rotating shafts or journals.