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
50 V60 HzR = 30 ΩL = 100 mH

A series RL circuit is connected to a 50 V (rms), 60 Hz supply. Find the magnitude of the impedance |Z|.

V = 50 V (rms)f = 60 HzR = 30 ΩL = 100 mH
|Z| = Ω
2.Easy
100 V200 HzR = 100 ΩL = 150 mH

A series RL circuit is connected to a 100 V (rms), 200 Hz supply. Find the rms voltage VL across the inductor.

V = 100 V (rms)f = 200 HzR = 100 ΩL = 150 mH
VL = V
3.Medium
230 V100 HzR = 15 ΩL = 20 mHI

A resistor and an inductor are connected in parallel across a 230 V (rms), 100 Hz supply. Find the magnitude of the impedance |Z|.

V = 230 V (rms)f = 100 HzR = 15 ΩL = 20 mH
|Z| = Ω
4.Medium
50 V200 HzR = 10 ΩL = 100 mHC = 22 µFI

A series RLC circuit is connected to a 50 V (rms), 200 Hz supply. Find the power factor cos φ of the circuit.

V = 50 V (rms)f = 200 HzR = 10 ΩL = 100 mHC = 22 µF
cos φ =
5.Hard
100 V500 HzR = 100 ΩL = 20 mHC = 22 µFI

A series RLC circuit is connected to a 100 V (rms), 500 Hz supply. Find the rms current I.

V = 100 V (rms)f = 500 HzR = 100 ΩL = 20 mHC = 22 µF
I = A
6.Hard
VfR = 2 ΩL = 200 mHC = 10 µF

A series RLC circuit has R = 2 Ω, L = 200 mH and C = 10 µF. Find its bandwidth B (the width of the band between the half-power frequencies), in Hz.

R = 2 ΩL = 200 mHC = 10 µF
B = Hz

Answer key

  1. 1. |Z| = 48.18 Ω
  2. 2. VL = 88.34 V
  3. 3. |Z| = 9.633 Ω
  4. 4. cos φ = 0.1111
  5. 5. I = 0.9002 A
  6. 6. B = 1.592 Hz

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