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
24 V60 HzR = 60 ΩL = 150 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 = 60 ΩL = 150 mH
|Z| = Ω
2.Easy
Vf = ?L = 10 mH

At what frequency f does a 10 mH inductor have a reactance of 500 Ω?

L = 10 mHXL = 500 Ω
f = Hz
3.Medium
Vf0​ = 2000 HzRL = 2 mHC = ?

A series RLC circuit with L = 2 mH must resonate at 2000 Hz. Find the capacitance C needed.

f0 = 2000 HzL = 2 mH
C = µF
4.Medium
24 V50 HzR = 60 ΩL = 200 mHI

A resistor and an inductor are connected in parallel across a 24 V (rms), 50 Hz supply. Find the phase angle φ of the impedance, in degrees (positive when the current lags the voltage).

V = 24 V (rms)f = 50 HzR = 60 ΩL = 200 mH
φ = °
5.Hard
10 Vf0​R = 10 ΩL = 10 mHC = 2.2 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 = 10 ΩL = 10 mHC = 2.2 µF
VL = V
6.Hard
230 V500 HzR = 60 ΩL = 200 mHC = 4.7 µFI

A series RLC circuit is connected to a 230 V (rms), 500 Hz supply. Find the rms current I.

V = 230 V (rms)f = 500 HzR = 60 ΩL = 200 mHC = 4.7 µF
I = A

Answer key

  1. 1. |Z| = 82.45 Ω
  2. 2. f = 7958 Hz
  3. 3. C = 3.166 µF
  4. 4. φ = 43.68 °
  5. 5. VL = 67.42 V
  6. 6. I = 0.4079 A

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