LC resonance, Q factor & bandwidth worksheet with answers

Free printable LC resonance, Q factor & bandwidth 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
C = 10 nF+−15 VL = 22 µHiL​

A 10 nF capacitor charged to 15 V is switched across an ideal 22 µH inductor. Find the peak current Imax in the circuit, in mA.

C = 10 nFV0 = 15 VL = 22 µH
Imax = mA
2.Easy
f|I|0.70715 kHzf1​f2​BW = ?

A tuned circuit resonates at 5 kHz and has a quality factor Q = 80. Find its bandwidth BW in Hz.

f0 = 5 kHzQ = 80
BW = Hz
3.Medium
V22 Ω4.7 mH1 nF

A series RLC circuit has R = 22 Ω, L = 4.7 mH and C = 1 nF. Find its quality factor Q.

R = 22 ΩL = 4.7 mHC = 1 nF
Q =
4.Medium
V10 Ω10 mH22 nF

A series RLC circuit has R = 10 Ω, L = 10 mH and C = 22 nF. Find its quality factor Q.

R = 10 ΩL = 10 mHC = 22 nF
Q =
5.Hard
V10 ΩLC = ?

Design a series RLC filter with a total resistance of 10 Ω, a resonance frequency of 50 kHz and a bandwidth of 1.25 kHz. Find the capacitance C in nF.

R = 10 Ωf0 = 50 kHzBW = 1.25 kHz
C = nF
6.Hard
f|I|0.7071f0​ = ?2 kHz2.2 kHzBW

The half-power frequencies of a resonance curve are 2 kHz and 2.2 kHz. Find the resonance frequency as their geometric mean, and then the quality factor Q.

f1 = 2 kHzf2 = 2.2 kHz
Q =

Answer key

  1. 1. Imax = 319.8 mA
  2. 2. BW = 62.5 Hz
  3. 3. Q = 98.54
  4. 4. Q = 67.42
  5. 5. C = 7.958 nF
  6. 6. Q = 10.49

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