Define potential energy difference between any two points.

Explanation

Electric potential difference between any two points in an electric field due to a point charge is defined as the difference in the electric potential energy acquired per unit positive test charge between these points.
Potential difference `=((1)/(4piepsi_(0)))(q)((1)/(r_(1))-(1)/(r_(2)))` where distance `r_(2) gt r_(1)`.