Red Seal Electrician Practice
AC theoryQuestion 970 of 1506

In a parallel R-C circuit, how is the total current found?

  1. By adding the branch current magnitudes as plain numbers
  2. By adding the branch currents as vectors
  3. By taking the larger branch current
  4. By dividing the supply voltage by the resistance only
Show answer

Correct answer: By adding the branch currents as vectors

Kirchhoff’s current law holds in AC, but the branch currents are 90 degrees apart and must be added as vectors.

Source: Lessons in Electric Circuits II: AC (Kuphaldt), 4.4: Parallel Resistor-Capacitor Circuits

Practice ac theory

Questions last reviewed: 18 October 2026