【判断题】年产6万吨以下的矿井采用单回路供电时,必须有备用电源;备用电源的容量必须满足排水、提升的要求;()
【判断题】为了保证系统运行电压的水平,系统拥有的无功电源必须满足正常电压水平下的无功需求,并留有必要的备用容量。
【单选题】DC Motors are electromechanical devices which use the interaction of magnetic fields and conductors to convert the ( 1) energy into rotary (2) energy.
A.
(1)mechanical (2)electrical
B.
(1)electrical (2)mechanical
C.
(1)electromagnetic (2)mechanical
D.
(1)mechanical (2)electromagnetic
【多选题】年产6万吨以下的矿井采用单回路供电时,必须有备用电源:备用电源的容量必须满足()等的要求。
【多选题】飞机库的消防水源必须满足()同时供水要求和最大用水量。
【简答题】A.He lacks time. B.He lacks willpower. C.He lacks sleep. D.He lacks medicine.
【简答题】The home lacks ( ) angle. (what type of angle)
【简答题】(1) interaction: (2) gossiper : (3) busy : (4) tension : (5)atmosphere : (6) direct:
【简答题】请朗读下列单词,练习好了以后,请语音提交 1 flatten 2 interaction 3 separation 4 capture 5 dynamics
【简答题】The home lacks what type of angle?