Graphite sheets are commonly used in introductory physics laboratories to model electric potential patterns for systems such as dipoles and parallel plates. Usually, silvered ink pens are used to draw patterns on the sheets and appropriate voltages are then applied. Quantitative experiments are often done at the intermediate level. Students are often puzzled by the failure of the patterns to confirm to the theoretical figure in the manual that came with the kit. I discuss measuring difficulties and some of the common theoretical methods for analyzing edge effects on the sheets.
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The spreadsheet can also be found at ⟨ww2.gannon.edu/cetl/felement_graphite.xls⟩.
© 2009 American Association of Physics Teachers.
2009
American Association of Physics Teachers
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