The potential energy between the two points is Q1×Q2/(4×pi×epsilon0×r) in joules. The voltage is the electric potential difference at a distance from a point, i.e. the voltage at charge point 2 is independent of the charge at point 2 (and vice versa) V at point 2 = Q1/(4×pi×epsilon0×r) in volts (where r is your 1 cm). Applying the charge at point 2, by multiplying, converts the potential difference into a potential energy.
The potential energy between the two points is Q1×Q2/(4×pi×epsilon0×r) in joules. The voltage is the electric potential difference at a distance from a point, i.e. the voltage at charge point 2 is independent of the charge at point 2 (and vice versa) V at point 2 = Q1/(4×pi×epsilon0×r) in volts (where r is your 1 cm). Applying the charge at point 2, by multiplying, converts the potential difference into a potential energy.
