“运动电荷在匀强磁场中受洛仑兹力作匀速圆周运动”是我们非常熟悉的也很重要的中学物理学内容,它本身源于电磁学,同时又与匀速圆周运动的内容有着天然的联系,还和数学知识(尤其是几何学)结合紧密,是一个十分重要的“物理模型”。此模型问题在历年的高考中 “Motion charge is uniformly and circularly moved by Lorentz force in a uniform magnetic field” is a very familiar and very important secondary school physics content. It itself originated from electromagnetics and has a natural connection with the content of uniform circular motion. It is also a very important “physical model” that is closely integrated with mathematical knowledge (especially geometry). This model problem in the college entrance examination over the years