Consider a long transmission line (4 km). Its a single conductor line with the inner conductor insulated. The outer shell is steel ground.
Consider two scenarios.
Scenario A: 120 V DC power supply, positive is hooked up to long transmission line, which is connected to 30 Ω load. Negative on the power supply is connected directly to the load.
Scenario B: 120 V DC power supply, positive AND negative are hooked up to long transmission line, which are both connected to the same load in Scenario A.
My question is, will scenario B draw more power or the same power than scenario A? The ground wire is taking a major shortcut in scenario A, so intuitively I would suspect that scenario B would take twice the power to drive the load then scenario A, since the ground wire is adding twice the length of effective wire length.
Excuse me if this is a rookie question, I just can't wrap my mind around it.