物理与工程2025，Vol.35Issue(3)：38-43,6.
有限大带电体和无限大带电体的电势
ELECTRIC POTENTIALS OF THE FINITE AND INFINITE CHARGED BODIES:ALSO DISCUSSING THE ELECTRIC POTENTIAL PROBLEM OF UNIFORMLY CHARGED INFINITELY LONG STRAIGHT WIRE
摘要
Abstract
Establishing clear and solid physical concepts and solving physical problems in a concise form are the fundamental objectives of physics teaching.This paper takes the calcula-tion of the electric potential of a uniformly charged infinite long straight wire as an example.Following the format of the textbook on"Electromagnetic Fields and Waves,"it introduces the electric potential through Helmholtz's theorem and derives the definition of electric poten-tial based on the work done by a unit positive charge in an electric field.By discussing the e-lectric fields of both finite and infinite charged bodies,it demonstrates that starting from the definition of electric potential avoids pathological mathematical definitions and can resolve the issue of divergent integrals caused by the misuse of the electric potential formula for finite charged bodies.Infinite charged bodies are the result of simplification,idealization,and rela-tivization,and thus,they cannot have their electric potential reference points selected at infin-ity like finite charged bodies.Instead,a finite distance must be chosen as the reference point.Once the reference point is determined,the electric potential of both finite and infinite charged bodies,like potential difference,becomes measurable.关键词
电动力学/电磁场与电磁波/电势的定义/有限大和无限大带电体/均匀带电无限长直导线/理想化和相对化Key words
electrodynamics/electromagnetic fields and wave/definition of electric potential/finite and infinite charged bodies/uniformly charged infinitely long straight wire/idealization and relativization引用本文复制引用
曹清华..有限大带电体和无限大带电体的电势[J].物理与工程,2025,35(3):38-43,6.基金项目
江苏大学高等教育教改研究课题(2023JGYB014) （2023JGYB014）
江苏大学课程思政教学改革研究课题(2022SZYB022). （2022SZYB022）
