5J30.10 - Ringing Circuit

Code Number:
Demo Title:
Ringing Circuit
Capacitor - Inductor Resonance
Area of Study:
Electricity & Magnetism
Storage Oscilloscope, Overhead Circuit Diagram, Ringing Circuit Demo Unit.

Attach the battery to the snap on battery harness which should always be stored unattached. Connect the BNC lead to the oscilloscope. The oscilloscope will need at least 5 to 10 minutes of warm-up for proper operation. The scope is always left on the proper settings as this is the only demo that this scope is used for. Charge the capacitor by holding down on the proper key switch. Press the buttons in the upper right hand corner of the oscilloscope to clear and reset the screen.  Press the reset button which is located in the lower right-hand side of the oscilloscope.  Discharge the capacitor through the inductor by holding down on the other key switch and observe the trace on the oscilloscope. The capacitance and/or the resistance may be changed to show the affect on the trace.

  • Patrick Doran, William Hawk, P. B. Siegel, "Measuring c With a LC Circuit", TPT, Vol. 52, # 6, Sept. 2014, p. 368.
  • Yaakov Kraftmakher, "Demonstrations with an LCR Circuit", TPT, Vol. 49, #3, Mar. 2011, p. 168.
  • Martin Gardner, "Curious Feedbacks", TPT, Vol. 32, #1, Jan. 1994, p. 59.
  • En-9, 10 :  Freier and Anderson,  A Demonstration Handbook for Physics.
  • R. W. Pohl, "Electrical Oscillations", Physical Principles of Electricity and Magnetism, p. 180.
  • Ron Hipschman, "Very Slow Electric Oscillations", Exploratorium Cookbook III, p. 155.1 - 155.4.
  • W. Bolton, "Discharge of a Capacitor Through an Inductor (1)", Book 4 - Electricity, Physics Experiments and Projects, 1968, p. 65-66.
  • W. Bolton, "Discharge of a Capacitor Through an Inductor (2)", Book 4 - Electricity, Physics Experiments and Projects, 1968, p. 67-68.

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