5D10.40 - Resistor Model - Random Walk

Code Number:
Demo Title:
Resistor Model - Random Walk
Resistor Theory and Function
Area of Study:
Electricity & Magnetism
Random Walk, Balls (Assorted Diameters).

Elevate one end of the random walk unit. Roll a ball bearing down through the pegs and observe the 'resistance' to it forward motion. Different effects can be observed by using balls with varying diameters and changing the elevation of the random walk.

  • Miles J. Dresser, "A Drude Resistance Simulation", TPT, Vol. 23, # 3, Mar. 1985, p. 151 - 154.
  • Mario Iona, "Teaching Electrical Resistance", TPT, Vol. 17, # 5, May 1979, p. 299.
  • Philip B. Allen, "Electrical Conductivity", TPT, Vol. 17, # 6, Sept. 1979, p. 362.
  • Donald Long, "Electrical Conduction in Solid", TPT, Vol.  7, # 5, May 1969, p. 264.
  • Genevieve DiBari, Liliana Valle, Reflilwe Tanah Bua, "Using Hexbugs TM to Model Gas Pressure and Electrical Conduction: A Pandemic-Inspired Distance Lab", AJP, Vol. 90, #11, Nov. 2022, p. 817.
  • Harold Weinstock, "Pinball Analog for Electrical Circuits", AJP, Vol. 31, #11, Nov. 1963, p. 887.
  • E-300:  "Bed of Nails with Steel Balls",  DICK and RAE Physics Demo Notebook.
  • Eg-1:  Freier and Anderson,  A Demonstration Handbook for Physics.
  • Borislaw Bilash II, David Maiullo, "Stopper My Flow", A Demo a Day: A Year of Physics Demonstrations, p. 270.

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