Can there be a potential difference between two adjacent conductors carrying the same charge?
If in two conductors flowing current is same then both may be considered in series. So Ohm's law becomes V∝R. i.e., if the resistances (which depends on ρ,1 and A ) are different then potential difference will be different. So there can be potential difference between two adjacent conductors carrying the same charge or current if either their length or area of cross-section (A) and resistivity are different.