7B35.10 - Crookes tubes

Hook the induction coil to the electrodes of the tube, turn on and adjust the power and the direction of the current of the coil. The Crookes tubes are designed to be evacuated during the above operation so that different patterns and characteristics may be observed.
Code Number:
7B35.10
Demo Title:
Crookes tubes
Condition:
Good
Principle:
Electron Beams and Properties
Area of Study:
Modern Astronomy
Equipment:
Large Crookes Tubes (1 to 3 ft. long), Small Crookes Tubes (Light bulb and others), Vacuum Pump, Induction Coil.
Procedure:

Hook the induction coil to the electrodes of the tube, turn on and adjust the power and the direction of the current of the coil. The Crookes tubes are designed to be evacuated during the above operation so that different patterns and characteristics may be observed. 

References:
  • Thomas B. Greenslade Jr., "Apparatus Named After Our Academic Ancestors - I", TPT, Vol. 48, # 9, December 2010, p. 604.
  • Carl Fields,  "Radiation from Video Display Terminals?",  TPT, Vol. 25, # 4, p. 213, April 1987.
  • Karl Parsons, "X-Ray Dosage from a Crookes' Tube", AJP, Vol. 35, #9, Sept. 1967, p. 890.
  • Ep-7, 9:  Freier and Anderson, A Demonstration Handbook for Physics.
  • S-150:  "Gas Discharge & Evacuated Tube",  DICK and RAE Demo Notebook.
  • "Crookes Tubes: How Safe Are They", PIRA News, Vol. 3 # 1, January 1988.
  • William S. Properzio, Ray C. Woodcock, and Sidney D. Heidersdorf, "X-Ray Emission from Cold-Cathode Gas Discharge Tubes Used for Educational Purposes", X-ray Exposure Control Laboratory, Division of Electronic Products, Feb. 1970.

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