A bell activated by the magnetic effect of an electric current. 由电流的磁效应作用的铃。
When strain waves pass through a ferromagnetic bar,owing to piezomagnetic effect,a nonuniform magnetic current will be stimulated by the strain wave simultaneously. 应变波通过铁磁性杆件时，由于压磁效应，会同时在杆件中激发出不均匀的磁流。
