I Why are field lines parallel in a uniform field?

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In a uniform electric field created by charged plates, the individual atomic charges generate radial fields that typically do not exhibit parallel field lines. However, the vector sum of these radial fields results in a uniform field where lines appear parallel. This phenomenon can be likened to wave propagation, where adjacent sources create a linear wave front, as explained by Huygens' principle. The charges on the plates remain stationary, leading to fields that are perpendicular to the surface without tangential components. Thus, the parallel nature of the field lines in a uniform field arises from the cumulative effect of these radial fields.
jackiepollock
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For a uniform field like this, I imagine the two plates that creates it are made of multiple atoms with charges, which are points sources that create radial fields. We know that radial fields don't have parallel fields lines, so how are parallel fields lines form when the field is made of various radial fields? Is it caused by the vector sums of these radial fields?

Screenshot 2021-08-03 at 20.51.09.png
 
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Hello,

Yes you have the right picture in mind. There is an analogy with waves: the summation of waves propagating in circles from adjacent sources generates a more or less linear wave front ( google huijgens principle ).

So on the edges of the plates the field lines will bulge outward a little bit## \ ##
 
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BvU said:
Hello,

Yes you have the right picture in mind. There is an analogy with waves: the summation of waves propagating in circles from adjacent sources generates a more or less linear wave front ( google huijgens principle ).

So on the edges of the plates the field lines will bulge outward a little bit## \ ##
Thank you!
 
jackiepollock said:
For a uniform field like this, I imagine the two plates that creates it are made of multiple atoms with charges, which are points sources that create radial fields. We know that radial fields don't have parallel fields lines, so how are parallel fields lines form when the field is made of various radial fields? Is it caused by the vector sums of these radial fields?

View attachment 287041
On the plate the charges are on the surface which can’t move because the field don’t have any tangential component along the surface. The vector sum of all the fields at all points are fields perpendicular to the surface.
 
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