由于产生原理不同,电磁感应问题中涉及到动生电动势和感生电动势两种计算.所谓动生电动势是指磁场不随时间变化,导体局部或者整体在磁场中运动时,其中的自由电荷受洛伦磁力而定向移动产生的电动势,此类问题较易找到等效电源所在位置,也较容易等效成学生熟悉的电路来解决.而另一种则是由随时间变化的磁场而产生的,称为感生电动势,随时间变化的磁场会产生涡旋电场,涡旋电场分布在整个空间中,包括磁场内部及外部,处于涡旋电场中的导体,其内部自由电荷 Due to different production principles, electromagnetic induction problems involve two kinds of calculations: the electromotive force and the induced electromotive force. The so-called electromotive force is the time when the magnetic field does not change with time. When the conductor moves partially or entirely in the magnetic field, the free charge is affected by Loren. Magnetic force and the electromotive force generated by directional movement, this kind of problem is easier to find the location of the equivalent power source, and it is easier to be equivalent to the circuit that the students are familiar with. The other kind is caused by the magnetic field that changes with time. To induce electromotive force, a magnetic field that changes over time generates a vortex electric field that is distributed throughout the space, including the inside and outside of the magnetic field, the conductor in a vortex electric field, and its internal free charge