GRE Conservation of Energy problem.

AI Thread Summary
The discussion revolves around the derivation of the electric potential formula, specifically why it is expressed as -K/2r^2. Participants are trying to understand the integration of the force F = K/r^3, questioning the origin of the factor of 2 in the denominator. The conversation references the standard integration rule for xn, applying it to the case where n = -3. Clarifications on the integration process and the resulting constants are sought to resolve the confusion. Understanding these mathematical principles is crucial for solving related physics problems.
PsychonautQQ
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Homework Statement


http://grephysics.net/ans/9277/87

Can somebody explain to me why the electric potential = -K/2r^2?
If you integrate Fdr and F = K/r^3, where does the 2 in the denominator come from?
 
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PsychonautQQ said:

Homework Statement


http://grephysics.net/ans/9277/87

Can somebody explain to me why the electric potential = -K/2r^2?
If you integrate Fdr and F = K/r^3, where does the 2 in the denominator come from?
Standard rules. What's the integral of xn.dx? Now put n = -3.
 
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