Pencil Leads, Ohm meter

 

Code Number: 5D10.16

Demo Title: Resistors - Characteristics of Pencil Lead Resistors

Condition: Good

Principle: Principles and Varieties of Resistors

Area of Study: Electricity & Magnetism

Equipment: 

Pencil Leads, Ohm meter.

Procedure:

Pencil lines drawn onto paper, or pencil lead can be used as resistors and in particular used for studies of cross sections.  One set of leads in the box have one lead sanded so that its cross section is 1/2 of the other.  Pencil leads of different diameters may also be obtained for the same demonstration.

References:

  • Vibhooti Shekhawat, "Graphite-Paper Circuit Elements: Resistor, Capacitor, and ¶ Value Estimation", TPT, Vol. 61, #2, Feb. 2023, p. 154.
  • Ricardo Medel-Esquivel, Isidro Gomez-Vargas, Ricardo Garcia-Salcedo, J. Alberto Vazquez, "A Simple Estimation of the Size of Carbon Atoms Using a Pencil Lead", TPT, Vol. 59, #6, Sept. 2021, p. 480.
  • Asuman Kucukozer, "Teaching the Factors Affecting Resistance Using Pencil Leads", TPT, Vol. 53, # 1, Jan. 2015, p. 38.
  • Chris Chiaverina, "Exploring Electric Circuits and Resistance Using Pencil Lead", TPT, Vol. 52, # 9, Dec. 2014, p. 570.
  • Samuel Derman and Aron Goykadosh, "A Pencil-and-Tape Electricity Experiment", TPT, Vol. 37, #7, Oct. 1999, p. 400.
  • Bobby Mercer, "Pencil Lead Lightbulb", Junk Drawer Physics, p. 142.
  • Rudolf F. Graf, "Controlling Your Current", Safe and Simple Electrical Experiments, p. 102.
  • Borislaw Bilash II, “Group 14: Metals versus Nonmetals“, A Demo A Day – A Year of Physical Science Demonstrations, p. 136.