It will be understood that electromagnets were the ticker's actuating agency. 弗兰克·刘易斯·戴尔.爱迪生的生平和发明.
In a shunt circuit with the receiving instrument he introduced electromagnets. 弗兰克·刘易斯·戴尔.爱迪生的生平和发明.
In such an arrangement there is practically the strength of two separate electromagnets. 伯莎M.克拉克.科学通论.
Electromagnets are used in place of simple magnets, and the armature, instead of being a simple coil, may be made up of many coils wound on soft iron. 伯莎M.克拉克.科学通论.
The strongest known magnets are electromagnets, which, as we have seen, are merely coils of wire wound on an iron core. 伯莎M.克拉克.科学通论.
The electromagnets and other actuating mechanism cannot be seen plainly in this figure, but are produced diagrammatically in Fig. 2, and somewhat enlarged for convenience of explanation. 弗兰克·刘易斯·戴尔.爱迪生的生平和发明.