Some basic electric potential questions

[kyoko]

[solved] some basic electric potential questions

Homework Statement

Find the electric potential established by the nucleus of a hydrogen atom at the mean distance of the circulating electron.

Homework Equations

V = - Integral of (E (dot) dL)
V = kq/r from r distance of a point charge

The Attempt at a Solution

well, I found on wikipedia that the atomic radius of a hydrogen atom is 25 * 10 ^ (-12) meters.
So I just used kq/r to find the potential and got the wrong answer.

Should I be using a different distance or a different equation?

thanks

 

[kyoko]

nvm I solved it I had to use r=5.29 * 10 ^ (-11) meters