Which statement best defines voltage drop?

Which statement best defines voltage drop?

• A. Voltage drop is the loss of voltage along a conductor due to resistance; a concern for long runs or high-current circuits.
• B. It is the increase of voltage along a conductor due to inductance.
• C. It is the total voltage supplied by the utility.
• D. It is the voltage difference between two points along a conductor when idle.

Answer: (A)

Voltage drop is the reduction in voltage that occurs as current flows through a conductor because of the wire’s resistance. As current travels along a length of wire, part of the electrical energy is dissipated as heat in the conductor, so the voltage at the far end is lower than at the source. The amount of drop grows with longer runs and with higher current, which is why long cables or high‑current circuits are a concern. The relationship is captured by V_drop ≈ I × R, where resistance increases with length and with smaller or colder conductor sizes, and with material properties. This matches the idea that voltage drop is caused by resistance along the path. The other statements aren’t accurate: inductance in a conductor doesn’t cause a net increase in voltage along the run; the utility provides the source voltage, not the drop itself; and with no current (idle) there’s essentially no voltage drop along the conductor.

Voltage drop is the reduction in voltage that occurs as current flows through a conductor because of the wire’s resistance. As current travels along a length of wire, part of the electrical energy is dissipated as heat in the conductor, so the voltage at the far end is lower than at the source. The amount of drop grows with longer runs and with higher current, which is why long cables or high‑current circuits are a concern. The relationship is captured by V_drop ≈ I × R, where resistance increases with length and with smaller or colder conductor sizes, and with material properties.

This matches the idea that voltage drop is caused by resistance along the path. The other statements aren’t accurate: inductance in a conductor doesn’t cause a net increase in voltage along the run; the utility provides the source voltage, not the drop itself; and with no current (idle) there’s essentially no voltage drop along the conductor.