Differentiating electrostatic force

AI Thread Summary
The discussion focuses on deriving the expression for potential energy between two particles in an ionic bond using Coulomb's law. The initial attempt involves integrating the force over distance, but there are concerns about the accuracy of the limits used in the integral. Participants emphasize the importance of understanding the reference point for potential energy, as it affects the integral's limits. Clarification on the correct approach to applying Coulomb's law is provided, highlighting the need for careful consideration of distance conventions. Overall, the conversation aims to refine the understanding of potential energy calculations in ionic bonds.
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Homework Statement


Obtain an expression for the potiential energy between to particles in an ionic bond at radius r0

Homework Equations


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

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 that's the answer, but I'm not sure and i don't have the actual answer available. Any help would be appreciated :)
 
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You'd better take a second look at Coulomb's law.
 
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.
 
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