角行程电动执行器“堵转”不会烧坏电动机的原因()
A.电动机功率一般比较小
B.电动机输出的力矩比较小
C.电动机转子电阻比较大
D.电动机转子电阻比较小
参考答案:C
Was it at the school _________ he spent his childhood? [ ]
A. that
B. where
C. which
D. what
如图所示,重为6N的长方体浸没在水中,上表面受到水的压力为4N,则物体的质量为_______kg,密度为__________㎏/m3 (g取10N/kg)。