How does electromagnetism tell us that there is an invisible circle at every point in space and time; what does that mean, if we could see them, what would that even look like?

Question

How does electromagnetism tell us that there is an invisible circle at every point in space and time; what does that mean, if we could see them, what would that even look like?

In: Physics

Answer 1

By invisible circles, do you mean the magnetic field?
It is not actually circles, it is just drawn like that to illustrate the field. in reality it is everywhere, at every single point and between every point. it has a direction and strength. Deep in space it might have almost 0 strength, where it is stronger on and near the earth, strong enough to align a compas needle along the field but weak enough that you can have an iron nail without it flying towards either pole.