If we place two objects, say electroscopes, charged to different potential side by side, charges will not move from one to the other, Now if  the two are connected using a wire or a conductor, the flow of charges takes palace. Charge will  flow as long as there is a difference of potential between the two conductors. The flow stops as soon as their potential become equal. This flow of electric charge is called electric current. The potential difference (P.D.) of one volt between two points is the measure of work done in moving one coulomb of charge across them.

Derived Formula & Unit Of Potential difference : -

Potential Difference (P.D.)  = Work  Done  /  Charged Moved = W/Q  = Joule/ Coulomb =  Volt.                                                                                                                     

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