AC impedance & phasors worksheet with answers

Free printable AC impedance & phasors worksheet: 6 problems from easy to exam level, with an answer key. Print it or save it as a PDF.

New worksheetPractise online with hints

For teachers: free to print, copy and use in class. Every new worksheet has new values and its own answer key. A link to ExamProblems on your course page is appreciated.

Name: ____________________   Date: ____________

1.Easy
120 V60 HzR = 15 ΩL = 250 mHI

A series RL circuit is connected to a 120 V (rms), 60 Hz supply. Find the rms current I.

V = 120 V (rms)f = 60 HzR = 15 ΩL = 250 mH
I = A
2.Easy
24 V60 HzR = 100 ΩL = 200 mH

A series RL circuit is connected to a 24 V (rms), 60 Hz supply. Find the magnitude of the impedance |Z|.

V = 24 V (rms)f = 60 HzR = 100 ΩL = 200 mH
|Z| = Ω
3.Medium
230 V50 HzR = 60 ΩL = 50 mHC = 47 µFI

A series RLC circuit is connected to a 230 V (rms), 50 Hz supply. Find the rms current I.

V = 230 V (rms)f = 50 HzR = 60 ΩL = 50 mHC = 47 µF
I = A
4.Medium
10 V50 HzR = 25 ΩL = 50 mHC = 10 µF

A series RLC circuit is connected to a 10 V (rms), 50 Hz supply. Find the phase angle φ of the impedance, in degrees (positive when the current lags the voltage).

V = 10 V (rms)f = 50 HzR = 25 ΩL = 50 mHC = 10 µF
φ = °
5.Hard
12 Vf0​R = 2 ΩL = 10 mHC = 1 µF

A series RLC circuit is driven by a 12 V (rms) source whose frequency is set to the resonant frequency of the circuit. Find the rms voltage VL across the inductor.

V = 12 V (rms)R = 2 ΩL = 10 mHC = 1 µF
VL = V
6.Hard
10 Vf0​R = 50 ΩL = 10 mHC = 0.1 µF

A series RLC circuit is driven by a 10 V (rms) source whose frequency is set to the resonant frequency of the circuit. Find the rms voltage VL across the inductor.

V = 10 V (rms)R = 50 ΩL = 10 mHC = 0.1 µF
VL = V

Answer key

  1. 1. I = 1.257 A
  2. 2. |Z| = 125.2 Ω
  3. 3. I = 2.896 A
  4. 4. φ = −85.28 °
  5. 5. VL = 600 V
  6. 6. VL = 63.25 V

Full step-by-step solutions: practise this topic on examproblems.com.