问题
选择题
— Which monkey is ___________?
— The yellow one.[ ]
A. small
B. big
C. bigger
答案
答案：C
搜题请搜索小程序“爱下问搜题”
— Which monkey is ___________?
— The yellow one.[ ]
A. small
B. big
C. bigger
答案：C
，此式表明三向异步电动机的调速方法有三种。即a改变电源频率f1；b改变旋转磁场的极对数P；c改变转差率s。