【简答题】某三相异步电动机,极对数p = 2,定子绕组三角形联结,接于50 Hz、380V 的三相电源上工作,当负载转矩为91 N·m 时,测得线电流为30 A,P1= 16 kW,n =1470 r/min,求该电动机带此负载运行时的效率为 %(结果保留1位小数)。
【简答题】某三相异步电动机,极对数p = 2,定子绕组三角形联结,接于50 Hz、380V 的三相电源上工作,当负载转矩为91 N·m 时,测得线电流为30 A,P1= 16 kW,n =1470 r/min,求该电动机带此负载运行时的效率为 %(保留一位小数)。
【单选题】Which of the following is good for the economy according to Eliot Spitzer?
A.
Law enforcement approach.
B.
Decisions open to question.
C.
The honour code among CEOs.
D.
Board oversight and self-regulation.
【单选题】For the economy to be in equilibrium , income must equal expenditure.
【简答题】基因工程是通过体外重组将甲生物体的基因转入乙受体生物体内进行表达的生物技术。获取目的基因的方法有: 、 、 、 。
【单选题】Which of the following have to be in equilibrium for the economy to be in equilibrium?
C.
the output and assets markets
D.
the savings and investment markets
E.
the goods and output markets
【单选题】The worst thing that could happen for the president and the Democrats is for the economy to continue to ( ) and they get blamed for it.
【单选题】周女士,因发热、关节疼痛,以类风湿性关节炎住院。护理措施错误的是?
【简答题】某三相4极笼型异步电动机,其定子绕组星形联结,该电动机的技术数据为:P N =11kW,U N1 =380V,n N =1430r/min,λ m =2.2,用它来拖动T z =0.8T N 的恒转矩负载运行。求: