- #1

- 1,395

- 0

http://i42.tinypic.com/9j2alv.gif

the charge on one small ring is

[tex]

dq=\frac{Qdx}{h}\\

[/tex]

the problem is with the distance squared part

its constantly changes

i dont know how to write in the distance square part

??

[tex]

E=\frac{kQ }{h} \int_{h+d}^{d}d x

[/tex]

and it a ring not a small partical

so the normal formula of a field kq/r^2

is not logical here