一台三相四极异步电动机，额定转差率是 0.04，若电源频率是50Hz，则电动机的转速为( )。

答案查看网，轻松搜题/搜资源

【单选题】【消耗次数：1】

① 1440r/min

② 1450r/min

③ 1000r/min

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