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I've been trying to define the electrostatic potential (V) for a while now, it's something that I've covered last year and now need to know what exactly it does mean, I came up with this and all I need is an answer to whether it's right or wrong, thank you.

The electrostatic potential of a point charge q is the amount of energy stored in a +1C charge after moving in an electric field sourced from q. (from infinity to r)

Note that negative values mean that energy is being released rather than stored.

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    $\begingroup$ Almost. The energy is not stored in the charge. You can say that it is stored in the system or perhaps the field, but a single object cannot store potential energy. $\endgroup$
    – garyp
    Commented Oct 23, 2019 at 13:13
  • $\begingroup$ Also please note that a charge of +1C can be huge compared to the field, so by adding (or removing) that charge, you will change the field. $\endgroup$
    – user112876
    Commented Oct 23, 2019 at 13:29
  • $\begingroup$ yes, it makes more sense if thought of as being stored/released from the field, I'll change it, @Ezze well that has just confused me, in this case would the law fail to give accurate results for something like a charge (q) which is a billion times smaller than +1C, I used this value instead of typing "positive unit charge". $\endgroup$
    – Essam
    Commented Oct 23, 2019 at 17:50
  • $\begingroup$ I just wanted to point out the fact that adding/removing charges to a field always changes the field itself, so it is a bit misleading to think about potential in terms of adding/removing stuff. $\endgroup$
    – user112876
    Commented Oct 24, 2019 at 13:59

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No, the electrostatic potential is not an energy. It is measured in Volts which is Joules/Coulomb.

The electrostatic potential is defined formally as the amount of work required to bring a point charge from infinity (or any agreed-upon point) to a point in space. I find the definition a bit misleading since it hints at thinking of the electrostatic potential in terms of energy.

Electrostatic potential is a property of space. In electromagnetism we often think about fields as a way to describe the effect of objects (charges of currents) on other objects at a distance. The electrostatic potential $V$ is a property of points inside the field, every point in space has a potential, and when this point has a charge in it, the potential energy of this charge is $qV$.

A nice way to think about it is the analogy with the gravitational field. The electrostatic potential is the equivalent of height with respect to earth. It is the potential energy of a point in space normalized by the field's source (which is the mass in this case).

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  • $\begingroup$ Thanks for pointing out, I should have typed "is numerically equal to" instead of "is", why would you find it misleading otherwise? Is "amount of work done to bring..." any different than "energy consumed to..." in this context? $\endgroup$
    – Essam
    Commented Oct 23, 2019 at 17:53
  • $\begingroup$ It is just that voltage is not energy, it is analogous to energy, but does not energy units and can't be compared to other energies. Think about upvoting answers if you like them ! $\endgroup$
    – Edgar
    Commented Oct 24, 2019 at 9:16

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