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In my textbook, I've read that electric potential is the work performed to carry one unit of positive charge to electric field from infinite distance.

We know that, W = Fs

So here the distance is infinity and W = F × infinity = infinity

But I have never seen potential's being infinity. So what is the problem here actually?

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    $\begingroup$ What happens if $F\propto1/s^2$? $\endgroup$
    – Kyle Kanos
    Commented Mar 4, 2019 at 16:35

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$W=Fs$ only when the force is constant. In general, $$ W=-\int_a^b \vec F\cdot d\vec r $$ for a path from $a$ to $b$. In the case of the electric potential, $$ W=-q \int_{\infty}^b \vec E\cdot d\vec r = -q\frac{Q}{4\pi\epsilon_0} \int_{\infty}^b \frac{1}{r^2}\cdot d\vec r=\frac{qQ}{4\pi\epsilon_0}\frac{1}{b} $$

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