SP212 Lab: Three Equipotential Surfaces and Electric Fields
Version: February 1, 2015
PHYSICS II
LAB 3
SP212
EquipotentialSurfacesandElectricFields
I. Pre‐LabAssignment
Thisweek,wewillrevisittheelectricfieldsimulatorprogramfromlablastweek. http://phet.colorado.edu/en/simulation/charges‐and‐fields. Readthroughthelabinstructions,andcompletethe“modelpredictions”foreachofthetwo
chargedistributions.Thesechargedistributionsaresimilartotheonesyouwillexplorein
lab.
Foreachofthechargegeometry(separately)completethefollowing:
1. Usingthesimulator,constructthechargedistributionasdescribedinthelab
instructions.
2. Plot6‐7equipotentialsurfaces.
3. Drawaquick,roughsketchofwhatisbeingdisplayed.Wearenotlookingfora
workofARTorafacsimile.Yourgoalistosketchsomethingyoucanuseduring
thelabtoremindyourselfwhatyousawduringthepre‐labassignment.Bring
bothofyoursketchestolab.
4. AnswerthequestionsaskedaboutthemodeledgeometryinsectionsA.1and
B.1ofthelabinstructions.
5. Dothefollowingonlyforthesinglepositivepointcharge:
a. MeasureVasafunctionofrforthepointcharge(asdefinedinthe
instructions),andrecordyourdatainanExcelspreadsheet.
b. Findthebestfitfunctiontoyourdata(Vasafunctionofr).Inashort
paragraph,explainwhatfunctionyouchoseandwhy.
YouwillneedtobefamiliarwithFig.25‐6andthesubsection“ACylindricalCapacitor”pages
721‐2ofourtextbook.Readthesepagesandbringyourbook(hardcopyorelectroniccopy)
tolab. Page 1 of 1