7B30.20 - Franck-Hertz

Plug the power supply into the oven observing the correct connections by symbol.  Turn the oven to about 200 degrees C and let warm up for at least 50 minutes.
Put the oscilloscope on xy plot and turn up the acceleration and heater knobs until peaks are observed.  By adjusting the acceleration, heater and RF knobs you should be able to fine tune the system to see at least 7 peaks and as many as 11.
Code Number:
7B30.20
Demo Title:
Franck-Hertz
Condition:
Good
Principle:
Quantization of Energy Absorption
Area of Study:
Modern Physics
Equipment:
Franck Hertz apparatus with oven and power supply, digital thermometer, and oscilloscope.
Procedure:

Plug the power supply into the oven observing the correct connections by symbol.  Turn the oven to about 200 degrees C and let warm up for at least 50 minutes.  

NOTE:  The heater thermostat on the unit allows the temperature to swing 10 to 20 degrees C under normal operation.  It is better to crank the thermostat to maximum, and then regulate the heater with a variac.  90 to 95 volts should give you a temperature of about 200 degrees C and keep it within two degrees of this.  Put the oscilloscope on xy plot and turn up the acceleration and heater knobs until peaks are observed.  By adjusting the acceleration, heater and RF knobs you should be able to fine tune the system to see at least 7 peaks and as many as 11.

References:
  • Kenneth H. Carpenter, "An automated Franck-Hertz experiment using an X-Y Recorder", AJP, Vol. #43, #2, Feb. 1975, p. 190.
  • Budford L. Williams, "The Franck-Hertz Experiment Using A Thyratron", TPT Vol. 6, # 6, Sept. 1968, p. 322.
  • Andrew Ahlgren, " A Modified Experiment with the Franck-Hertz Apparatus", TPT, Vol. 2, # 6, Sept. 1964, p. 282.
  • Daniele Faccio, Matteo Clerici, Davide Tambuchi, "Revisiting the 1888 Hertz Experiment", AJP, Vol. 74, # 11, Nov. 2006, p. 992. 
  • Gerald Rapior, Klaus Sengstock, Valey Basv, "New Features of the Franck-Hertz Experiment", AJP, Vol. 74, # 5, May 2006, p. 423.
  • W. Fedak, D. Bord, C. Smith, D. Gawrych, and K. Lindeman, "Automation of the Franck-Hertz Experiment and the Tel-X-Ometer X-Ray Maching Using LABVIEW", AJP, Vol. 71, # 5, May 2003, p. 501.
  • G. F. Hanne, "What Really Happens in the Franck-Hertz Experiment with Mercury?", AJP, Vol. 56, # 8, Aug. 1988, p. 696.
  • F. H. Liu, "Franck-Hertz Experiment With Higher Excitation Level Measurements", AJP, Vol. 55, # 4, Apr. 1987, p. 366.
  • D. R. A. McMahon, "Elastic Electron-Atom Collision Effects in the Franck-Hertz Experiment", AJP, Vol. 51, #12, Dec. 1983, p. 1086.
  • Wendell J. Caley, Jr., "Suggestions on 'An Automated Franck-Hertz Experiment'", AJP, Vol. 40, # 12, Dec. 1972, p. 1877.
  • R.E. Adelberger, K. F. Kinsey, "An Automated Franck-Hertz Experiment", AJP, Vol. 40, # 2, Feb. 1972, p. 349.
  • Bailey L. Donnally, "Comparison of Franck-Hertz Tubes and Apparatus", AJP, Vol. 34, #4, Apr. 1966, p. 366.
  • J. Rosenfeld and C. Tyler, "Homemade Franck-Hertz Tube",  AJP, Vol. 33, # 10, Oct. 1965, p. 849.
  • Yaakov Kraftmakher, "6.5, Franck-Hertz Experiment", Experiments and Demonstrations in Physics, ISBN 981-256-602-3, p. 397.
  • Keithley Instruments, "Physics Experiment # 2: Franck-Hertz Experiment", Series I.
  • Keithley Instruments, Paul W. Zitzewitz, "Physics Experiment # 1: Franck-Hertz Experiment", Series II.
  • W. Bolton, "The Controlled Excitation of Spectra", Book 3 - Atomic Physics, Physics Experiments and Projects, 1968, p. 24-26.

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