The Coulomb potential energy between two point charges is defined as:(adsbygoogle = window.adsbygoogle || []).push({});

V=[(q_1)(q_2)]/[(k*r)]

Suppose that you have two equal, like charges at a distance L, then V_like=q^{2}/(k*L)

Similarly, for two equal, opposite charges, V_opp=-q^{2}/(k*L)=-V_like

Both situations experience a force of equal magnitude (just opposite directions), yet V_opp<V_like? Shouldn't the two potential energies be equal?

By analogy with a mechanical spring, a weight that is left of the equilibrium position experiences a force of equal magnitude but opposite direction to a weight on the right of the equilibrium position. This is similar to the potential energy above. However, in this case, V_left=V_right, since the spring potential energy is:

V = 0.5kx^{2}

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# Coulomb Potential Energy - discrepancy between like and opposite charges

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