Finding work to move a point charge to the center of a thin ring.

[zbou]

1. Find the work required to move a point charge from infinitely far away to the center of a thin ring.

The point charge is q= 1nanocoulomb.
The rings charge is Q= 2 nanoC.
The ring has a radius r=2m.

Homework Equations

U= qV
W= -U

Thoughts
I think the first thing to consider is the field E created by the ring. I also know that this problem should be able to be solved with a single integral.

I don't really know where to start.

Thanks in advance

 

[tiny-tim]

welcome to pf!

hi zbou! welcome to pf!

the work done for the whole will be the sum of the work done for each part

 

[nasu]

I don't really know where to start.

Thanks in advance

How about calculating the potential in the center of the ring?