Red Seal Electrician Practice
DC circuitsQuestion 684 of 1506

An electrician needs an unknown voltage between two points in a complex circuit. All the other voltages around a loop through those points are known. What method gives the answer?

  1. Write a KVL equation for the loop and solve for the unknown
  2. Measure the current and multiply by the wire length
  3. Write a KCL equation at the nearest junction
  4. Add all resistances and divide by the supply voltage
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Correct answer: Write a KVL equation for the loop and solve for the unknown

KVL lets you find the one missing voltage in a loop when all the others are known.

Source: Lessons in Electric Circuits I: DC (Kuphaldt), 6.2: Kirchhoff’s Voltage Law (KVL)

Practice dc circuits

Questions last reviewed: 18 October 2026