1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Differentiating electrostatic force

  1. Feb 13, 2013 #1
    1. The problem statement, all variables and given/known data
    Obtain an expression for the potiential energy between to particles in an ionic bond at radius r0

    2. Relevant equations
    Coloumb's laws: F = (-k * q1 * q2)/r-1

    3. The attempt at a solution
    I think that if i do U = r00 F(r)dr = [k * q1 * q2 * r-1]r00 = k * q1 * q2 * r0-1, Then thats the answer, but i'm not sure and i don't have the actual answer available. Any help would be appreciated :)
  2. jcsd
  3. Feb 13, 2013 #2


    User Avatar

    You'd better take a second look at Coulomb's law.
  4. Feb 13, 2013 #3


    User Avatar
    Homework Helper

    well, if you want to get an answer using the (non-quantum) coulomb interaction, then you are on the right track. Your answer is not quite right. Think about what the distance is, when the potential is zero. (There is a convention to this). And this choice will influence your decision of the limits of your integral.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook