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
Vf = ?L = 100 mH

At what frequency f does a 100 mH inductor have a reactance of 100 Ω?

L = 100 mHXL = 100 Ω
f = Hz
2.Easy
24 V50 HzR = 40 ΩL = 150 mHI

A series RL circuit is connected to a 24 V (rms), 50 Hz supply. Find the rms current I.

V = 24 V (rms)f = 50 HzR = 40 ΩL = 150 mH
I = A
3.Medium
120 V500 HzR = 10 ΩL = 20 mHC = 10 µFI

A series RLC circuit is connected to a 120 V (rms), 500 Hz supply. Find the real power P taken from the supply.

V = 120 V (rms)f = 500 HzR = 10 ΩL = 20 mHC = 10 µF
P = W
4.Medium
24 V100 HzR = 100 ΩL = 250 mHC = 1 µF

A series RLC circuit is connected to a 24 V (rms), 100 Hz supply. Find the phase angle φ of the impedance, in degrees (positive when the current lags the voltage).

V = 24 V (rms)f = 100 HzR = 100 ΩL = 250 mHC = 1 µF
φ = °
5.Hard
12 V1000 HzR = 50 ΩL = 150 mHC = 2.2 µF+−VC​

A series RLC circuit is connected to a 12 V (rms), 1000 Hz supply. Find the rms voltage VC across the capacitor.

V = 12 V (rms)f = 1000 HzR = 50 ΩL = 150 mHC = 2.2 µF
VC = V
6.Hard
230 V200 HzR = 60 ΩL = 50 mHC = 4.7 µF+−VC​

A series RLC circuit is connected to a 230 V (rms), 200 Hz supply. Find the rms voltage VC across the capacitor.

V = 230 V (rms)f = 200 HzR = 60 ΩL = 50 mHC = 4.7 µF
VC = V

Answer key

  1. 1. f = 159.2 Hz
  2. 2. I = 0.3883 A
  3. 3. P = 135.7 W
  4. 4. φ = −86.01 °
  5. 5. VC = 0.996 V
  6. 6. VC = 318.6 V

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