College of Liberal Arts & Sciences
5C20.60 - Displacement Current
Hook the wave generator to an amplifier, and then connect the output of the amplifier to the parallel plate capacitor. Connect the sensing coil to the input of the other amplifier which is connected to a speaker. An amplified frequency of about 50 Hz going into the capacitor works well. Move the sensing coil around the capacitor plates. Notice that the coil only picks up a signal when held in the correct polarized position.
EXPERIMENTAL NOTES:
Run this at a frequency of 1000 to 3000 Hz. Use the smaller set of parallel plates. The current setup does not need the "Clamp box". Channel L volume on the Pyle Amplifier should be up half way. Sensor volume on the other amplifier should be up all the way. NOTE: We are probably hearing electrostatic components and not the true displacement current.
- Carl, E. Mungan, "Surface Currents on the Plates of a Charging Capacitor", TPT, Vol. 59, #2, Feb. 2021, p. 86.
- Joaquim Anacleto, J.M. Ferreira, "Comment on 'Magnetic Field Due to a Finite Length Current-Carrying Wire Using the Concept of Displacement Current'", TPT, Vol. 53, # 2, Feb. 2015, p. 68.
- Robert Buschauer, "Magnetic Field Due to a Finite Length Current-Carrying Wire Using the Concepts of Displacement Current", TPT, Vol. 52, # 7, Oct. 2014, p. 413.
- Robert Buschauer, "Derivation of the Biot-Savart Law from Ampere's Law Using the Displacement Current", TPT, Vol. 51, # 9, Dec. 2013, p. 542.
- Gary Reich, "An Alternative Introduction to Maxwell's Displacement Current", TPT, Vol. 51, # 8, Nov. 2013, p. 485.
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- Mark A. Heald, "On Maxwell's Displacement Current - II", TPT, Vol. 38, # 6, Sept. 2000, p. 329.
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- A. P. French, "Is Maxwells's Displacement Current a Current?", TPT, Vol. 38, # 5, May 2000, p. 274.
- Marcos G. Rizzotto, "Visualizing Displacement Current - A Classroom Experiment", TPT, Vol. 37, # 7, Oct. 1999, p. 398.
- R. W. Pohl, "The Displacement Current of the Dipole. The Radiation of Free Electric Waves", Physical Principles of Electricity and Magnetism, p 323.
- R. W. Pohl, "Electric Fields and Magnetic Fields", Physical Principles of Electricity and Magnetism, p 118.
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- W. G. V. Rosser, "Displacement Current in Maxell's Equations", AJP, Vol. 43, # 6, June 1975, p. 502.
- Thomas R. Carver, Jan Rajhel, "Direct 'Literal' Demonstration of the Effect of a Displacement Current", AJP, Vol. 42, # 3, March 1974, p. 246.
- H. L. Armstrong, "Comment of an Experiment Supposed to Show Displacement Current", AJP, Vol. 33, # 6, June 1965, p. 512.
- Hans Meissner, "The Meaning of Experiments Designed to Demonstrate Displacement Current", AJP, Vol. 33, # 6, June 1965, p. 512.
- Robert M. Whitmer, "Calculation of Magnetic and Electric Fields from Displacement Currents", AJP, Vol. 33, # 6, June 1965, p. 481.
- Hans Meissner, "Demonstration of Displacement Current", AJP, Vol. 32, #12, Dec. 1964, p. 916.
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