帶電粒子在磁場中運動的多解性問題解析

盧文福

摘 要：帶電粒子只在洛倫茲力作用下做勻速圓周運動，但往往會因帶電粒子的電性不確定、磁場的方向不確定、初速度大小不確定、初速度方向不確定、運動的周期性等原因形成多解問題，因而教師必須指導學生通過分類討論的方式，在綜合判斷的基礎上優化解題路徑，從而實現高中物理學習的減負增效。

關鍵詞：高中物理;磁場;帶電粒子;洛倫茲力;勻速圓周運動

中圖分類號：G633.7 文獻標志碼：A 文章編號：1008-3561（2020）22-0116-02

Analysis of Multiple Solutions of Charged

Particle Motion in Magnetic Field

Lu Wenfu

（No.1 Middle School of Changting County， Fujian Province， Changting 366300， China）

Abstract： Charged particles only do uniform circular motion under the action of Lorentz force， but they often form multiple solution problems due to the uncertainty of the electric properties of charged particles， the direction of magnetic field， the size of initial velocity， the direction of initial velocity， and the periodicity of motion. Therefore， teachers must guide students to optimize the solution path on the basis of comprehensive judgment by means of classified discussion Path， so as to achieve high school physics learning burden reduction and efficiency.

Key words： high school physics; magnetic field; charged particles; Lorentz force; uniform circular motion