When a charged particle is in a magnetic field, it tends to travel along that field's lines of force, spiralling as it goes.
当一个带电微粒在磁场中时，它会倾向于沿着磁力线螺旋运动。
In March of that year James Clerk Maxwell, a Scottish physicist, published the first piece of a four-part paper entitled "On physical lines of force".
那一年3月份的时候，一位苏格兰物理学家，詹姆斯·克拉克·麦克斯韦，发表了他论文《论物理的力线(On physical lines of force)》四部分的第一部分。
In March of that year James Clerk Maxwell, a Scottish physicist (pictured above), published the first piece of a four-part paper entitled "On physical lines of force".
在那一年的三月，詹姆斯·克拉克·麦克斯韦，一个苏格兰物理学家(见上图)，发表了题为《论物理的力线》论文四个部分中的第一个部分。
It has been suggested that birds can sense the magnetic lines of force stretching from the north to south magnetic poles of the earth, and so direct themselves.
有人认为，鸟类能觉察得出地球自北向南磁极的磁力线，因而能为自己导向。
The magnetic lines of force don't exist , they are defined by scientists.
磁力线并不存在，它是由科学家所定义。
A changed particle moves along the lines of force of a magnetic field, spiraling as it goes.
带电粒子沿磁力线运动时就会发生回转。
The existence of electric current in the conductor(not closed)which is cut-ting the magnetic lines of force(B-lines) variably in the magnetic field is pointed out, and the acceleration is discussed.
指出了在磁场中做变速切割磁力线（线）运动的导体（不闭合）中有电流存在，讨论了其运动加速度。
The existence of electric current in the conductor(not closed)which is cut-ting the magnetic lines of force(B-lines) variably in the magnetic field is pointed out, and the acceleration is discussed.
指出了在磁场中做变速切割磁力线（线）运动的导体（不闭合）中有电流存在，讨论了其运动加速度。
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