The abstract nature of electric potential difference (voltage) can make it a difficult concept to grasp, but understanding the relative nature of voltage is central to developing a conceptual understanding of electric circuits. In laboratory situations, I see these conceptual difficulties manifest when students have difficulty placing voltmeter probes appropriately or struggle to interpret unexpected multimeter readings, such as negative voltages. I developed this lab activity to reinforce the relative nature of electric potential difference and to provide students with a concrete understanding of what a voltmeter measures, including the significance of the placement of each multimeter probe.
References
1.
R.
Cohen
, B.
Eylon
, and U.
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,” Am. J. Phys.
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, 407
(May
1983
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L. C.
McDermott
and P.
Shaffer
, “Research as a guide for curriculum development: An example from introductory electricity, part I: Investigation of student understanding
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More information on Modeling Instruction can be found on the website of the American Modeling Teachers’ Association, http://modelinginstruction.org/.
4.
From sources including PASCO scientific, 10101 Foothills Blvd., Roseville, CA 95678-9011 or http://pasco.com (PASCO PK-9025).
5.
J.
Phillips
, J.
Sanny
, D.
Berube
, and A.
Hoemke
, “Beyond the point change: Equipotential surfaces and electric fields of various charge configurations
,” Phys. Teach.
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, 71
(Feb.
2017
).© 2018 American Association of Physics Teachers.
2018
American Association of Physics Teachers
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