We describe an adjustable parallel-plate capacitor apparatus designed for use in an undergraduate laboratory that permits precise variation of plate separation distances and overlap area. Two experiments are performed with the device to test the ideal capacitor formula derived from Gauss's Law. After correcting for edge effects and minor plate tilt, the device yields capacitance values within 3% of theoretical values.
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The PhET Interactive Simulations project is a product of the University of Colorado, Boulder, and is available online at <http://phet.colorado.edu>.
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A copy of the described device can be purchased by submitting an inquiry to <[email protected]>.
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As aforementioned, capacitance was measured with a precision of . Over the plate separation distances utilized, measured capacitances ranged between 59 and 394 pF, yielding the stated percentage error.
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2016
American Association of Physics Teachers
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