Ground potential

Representative circuit

The circuit diagram illustrates a simple ground loop. Circuit 1 (left) and circuit 2 (right) share a common path to ground of resistance ${\displaystyle \scriptstyle R_{G}}$. Ideally, this ground conductor would have no resistance (${\displaystyle \scriptstyle R_{G}=0}$), yielding no voltage drop across it (${\displaystyle \scriptstyle V_{G}=0}$), keeping the connection point between the circuits at a constant ground potential. In that case, the output of circuit 2 is simply ${\displaystyle \scriptstyle V_{\text{out}}=V_{2}}$.