Why Is There a Maximum Electric Field Point Outside a Charged Ring?

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Brad_1234
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In a uniformly charged ring of radius r, if there is an imaginary line from the center of the ring extending outward
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At the center of the ring I am told the charges cancel so the net charge is zero. And at infinity, the charge is so small it approaches zero.

Going out from the ring, there is some point X where the charge is greatest.

Why does this effect take place? How to figure out the field energy lines that have an effect on point X?

tia
 
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You can work this out just using coulombs law. Work out the force on a particle at a distance s due to an infinitismal point of the ring and then integrate around the ring. If you do it right you'll get.
[tex]E=K\frac{qz}{(z^2+R^2)^\frac{3}{2}}[/tex]
where q is the total charge on the ring and z is the distance along the perpendicular axis.
I don't think this really answers your question but perhaps if you plot it, it might be of some help. It at least explains why there is a point where the electric field is at a maximum.