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
12 V100 HzR = 150 ΩC = 47 µF

A series RC circuit is connected to a 12 V (rms), 100 Hz supply. Find the magnitude of the impedance |Z|.

V = 12 V (rms)f = 100 HzR = 150 ΩC = 47 µF
|Z| = Ω
2.Easy
V200 HzL = 2.2 mH

Find the reactance XL of a 2.2 mH inductor at 200 Hz.

L = 2.2 mHf = 200 Hz
XL = Ω
3.Medium
120 V200 HzR = 20 ΩL = 250 mHC = 2.2 µF

A series RLC circuit is connected to a 120 V (rms), 200 Hz supply. Find the phase angle φ of the impedance, in degrees (positive when the current lags the voltage).

V = 120 V (rms)f = 200 HzR = 20 ΩL = 250 mHC = 2.2 µF
φ = °
4.Medium
Vf0​ = 50 HzRL = 5 mHC = ?

A series RLC circuit with L = 5 mH must resonate at 50 Hz. Find the capacitance C needed.

f0 = 50 HzL = 5 mH
C = µF
5.Hard
100 V1000 HzR = 60 ΩL = 20 mHC = 100 µFI

A series RLC circuit is connected to a 100 V (rms), 1000 Hz supply. Find the rms current I.

V = 100 V (rms)f = 1000 HzR = 60 ΩL = 20 mHC = 100 µF
I = A
6.Hard
12 Vf0​R = 2 ΩL = 20 mHC = 4.7 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 = 20 mHC = 4.7 µF
VL = V

Answer key

  1. 1. |Z| = 153.8 Ω
  2. 2. XL = 2.765 Ω
  3. 3. φ = −67.19 °
  4. 4. C = 2026 µF
  5. 5. I = 0.7256 A
  6. 6. VL = 391.4 V

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