随着电力电子技术的发展,驱动电机的电力控制的体积越来越小,可实现高速高精度控制是()的一个重要特点。 ["电机","传感器","机械"]
走向断层
倾向断层
比较两组测定结果的精密度() 甲组:0.19%,0.19%,0.20%,0.21%,0.21% 乙组:0.18%,0.20%,0.20%,0.21%,0.22% ["A、甲、乙两组相同","B、甲组比乙组高 ","C、乙组比甲组高","D、无法判"]
力学之父阿基米得说过:“假如给我一个支点,我就能推动地球”,就非常形象地描述了()省力原理。 ["杠杆","轮与轴机械","斜面"]
斜向断层