The typical equipotential lab involves students sampling points in an electrode configuration: they move the probe around until they find a series of points with the same potential. Other authors have highlighted some difficulties with the traditional lab approach: most do not allow real-time visualization of equipotential lines, and students often seem to rely conceptually on single point charge equipotential models or Coulomb’s laws. I propose a different approach to the parallel plate lab: Students are directed to set up a grid of equally spaced points between parallel plates. Students measure and record probe voltages in a spreadsheet and analyze voltages as a function of x and y. I demonstrate typical results and briefly discuss possible extensions.

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Jeffrey A.
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, and
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,”
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2.
Abhilash
Nair
and
Vashti
Sawtelle
, “
Real-time visualization of equipotential lines using the IOLab
,”
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56
,
512
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(
2018
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