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The total work done to bring all the charges constituting a body from infinity to the body one by one is called the electrostatic potential energy of the body. And if I divide the expression of electric potential energy by the charge on the body, I will get the electric potential of the body. What is the physical significance of electric potential like electric potential energy ?

And I think the definitions of electric potential energy and self-energy are same, is there any difference between self-energy and electric potential energy of a system ?

Please correct me if I am understanding something wrong

Edit: If we bring a positively charged conductor near a negatively conductor, the potential of positively charged conductor Will decrease and that of the negatively charged conductor will increase.

That is understandable, but why after doing this more charge is required to raise the potential of positively charged conductor by 1V ?

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When you divide the electrostatic potential energy of a charged body by its total charge, you don't "get the electric potential of the body".

(1) If the body is not a conductor, there is no single electric potential of the whole body because it will, in general, differ for different locations on the body.

(2) The electric potential at a certain point in space (or on a body) is the work performed on a unit charge by bringing it from infinity to this location.

(3) If the charged body is a conductor, and thus has a single electric potential, its electrostatic potential energy is NOT the same as its electric potential times its charge. This can be easily seen for the example of a conducting sphere with a capacitance $C=4π\epsilon_0R$. When its is charged with a charge $Q$, its electric potential $V$ will be $$V=Q/C$$ so that its electric potential times its charge is $$QV=Q^2/C$$ Its electrostatic potential energy W, however, is only half of this: $$W=QV/2=Q^2/(2C)$$

(4) Considering only classical electrostatic interaction between charges, the electrostatic potential energy of any charged body is identical to its "self-energy".

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  • $\begingroup$ Thank you, sir, for your answer; it cleared all of my problems. Could you please address a small query I added to the question? $\endgroup$
    – Peter swift
    Commented May 15 at 14:22
  • $\begingroup$ You are qualitatively correct that bringing the second, negatively charged conductor close to the first one you lower its positive potential. But you have also increased its effective capacitance with respect to the environment when the second conductor was far away. Thus you need to add a higher positive charge to it to increase its potential by 1 Volt. To accurately analyze problems with differently charged conductors , you usually use the capacitance matrix (en.wikipedia.org/wiki/Capacitance) , or coefficients of potential (en.wikipedia.org/wiki/Coefficients_of_potential). $\endgroup$
    – freecharly
    Commented May 15 at 20:08
  • $\begingroup$ @Peterswift See my above comment answering your small query added to your edited question. $\endgroup$
    – freecharly
    Commented May 15 at 20:15

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