Calculating Net PE in Ions: A & B Constants

AI Thread Summary
The discussion centers on the calculation of net potential energy in ions, expressed as PE(r) = A r^m + B r^n, where A and B are proportionality constants. Participants seek clarification on the nature of these constants and request resources for further understanding. The conversation also touches on the equation for electrostatic forces between charged particles, F = kE*q1*q2/r^2, and how to derive work done in moving a charge from infinity to a point R. The integration of this force leads to an expression for potential energy change, highlighting the relationship between force, work, and potential energy. Overall, the thread emphasizes the importance of understanding these foundational concepts in physics.
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The general expression for calculating net potential energy in ion is:

PE (r) = A r^m + B r^n

where A & B are proportionality constants.

What exactly are these constants??
Could anyone point me to correct resources??
I'm new at this forum and very interested in learning physics.?
 
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I don't know if I'm entirely clear on what you're asking; make sure you're proofreading your posts and being as descriptive as possible. Taking my best guess at your question, the equation for electrostatic attraction or repulsion between two charged particles is:
(Sorry if you don't know calculus)
F=kE*q1*q2/r2
where q is charge, kE is the proportionality constant(permeability of free space/4pi), and r is distance.
If we assume the particle to have 0 potential energy at infinite distance, (defining it as the zero level), and the definition of work we can then create an expression describing the work done moving a particle of charge q from infinity to R.
W=\intF dr (from infinity to R)
Substituting and integrating gives:
W=[-1*kE*q1*q2/r](inf to R)
W=-1*kE*q1*q2/R
\DeltaPE=PEF-PEI
W=kE*q1*q2(1/RF-1/RI)
 
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