A.電壓 B.磁場(chǎng) C.電流 D.旋轉(zhuǎn)磁場(chǎng)
A.定子鐵芯 B.轉(zhuǎn)子鐵芯 C.轉(zhuǎn)子 D.定子磁場(chǎng)
A.45° B.90° C.120° D.135°