In the scenarios described, what is the voltage at the end of the line when the loads are 600A and 1200A?

• A. 120V
• B. 240V
• C. 480V
• D. 600V

Answer: (A)

In a setup where multiple loads are connected in parallel to a fixed-voltage source, the voltage across each load—and at the end of the line—stays the same as the source voltage. The currents in each branch can be large (600 A and 1200 A in this case), but that doesn’t change the voltage that the source maintains across the line, as long as the supply is stiff and the line impedance is negligible (or the voltage drop is accounted for but not enough to alter the end voltage here).

So the end-of-line voltage remains 120 V because the supply is regulating the voltage to that level, regardless of the total current drawn (which is 1800 A in total). The other voltage values would only apply if there were a different source voltage or significant voltage drop due to line resistance that isn’t part of this ideal assumption.