按汽流流动方向的不同,凝汽器可分为四种,目前采用较多的是() ["汽流向下式","汽流向上式","汽流向心式","汽流向侧式"]
力产生加速度时,引起受力物体运动状态的改变。()
利用杠杆撬重物,省力的方式是() ["动力臂大于阻力臂","动力臂小于阻力臂","动力臂等于阻力臂","B和C都正确"]
低碳钢的含碳量小于()% ["0.2","0.25","0.5","0.6"]
为了防止和消除轴承油膜振荡,下列叙述错误的是() ["增大比压","消除转子不平衡重量","减小轴径与轴瓦间的接触角","提高润滑油的黏度"]
检修无铰链型离心式调速器应检查哪些部位?