下列说法中正确的是A.磁场和磁感线都是真实存在的B.电动机工作

下列说法中正确的是
A.磁场和磁感线都是真实存在的
B.电动机工作时是将电能转化为动能
C.扬声器、电磁继电器、电铃都应用了电磁铁
D.磁极间的相互作用是通过磁场发生的

答案

BCD解析:

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