{"title":"A Spherical Version of Feynman's Static Field Momentum Example","authors":"Oliver Davis Johns","doi":"10.1088/1361-6404/ad0aa4","DOIUrl":null,"url":null,"abstract":"Abstract The Feynman demonstration that electromagnetic field momentum is real-even
for static fields-can be made more pedagogically useful by simplifying
its geometry. Instead of Feynman's disk with charged balls on its
surface, this article uses the geometry of a hollow non-conducting
sphere with uniform surface charge density. With only methods available
in a typical upper-division electrodynamics course, the initial field
angular momentum and the final mechanical angular momentum can then
be calculated in closed form and shown to be equal.
","PeriodicalId":50480,"journal":{"name":"European Journal of Physics","volume":null,"pages":null},"PeriodicalIF":0.6000,"publicationDate":"2023-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"European Journal of Physics","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1088/1361-6404/ad0aa4","RegionNum":4,"RegionCategory":"教育学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q4","JCRName":"EDUCATION, SCIENTIFIC DISCIPLINES","Score":null,"Total":0}
引用次数: 0
Abstract
Abstract The Feynman demonstration that electromagnetic field momentum is real-even
for static fields-can be made more pedagogically useful by simplifying
its geometry. Instead of Feynman's disk with charged balls on its
surface, this article uses the geometry of a hollow non-conducting
sphere with uniform surface charge density. With only methods available
in a typical upper-division electrodynamics course, the initial field
angular momentum and the final mechanical angular momentum can then
be calculated in closed form and shown to be equal.
期刊介绍:
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