单选题The nameplate of an AC non-synchronous motor shows that running speed is 1460r/minfrequency 50HzYou can infer that the number of magnetic poles is（）A2B4C6D8
单选题
The nameplate of an AC non-synchronous motor shows that running speed is 1460r/minfrequency 50HzYou can infer that the number of magnetic poles is（）
A
2
B
4
C
6
D
8
参考解析
解析：
暂无解析
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