在教学过程中我们会碰到各种示意图 ,比如受力图、电路图、光路图等 ,它能使复杂的物理问题直观化、简单化。1　画运动过程示意图 ,找几何关系。例 1　如图 1所示 ,一带正电的质子从O点垂直射入 ,速度为v0 ,两个板间存在垂直纸面向里的匀强磁场 ,已知两板之间距离为d ,板长为d In the teaching process, we will encounter various schematic diagrams, such as force diagrams, circuit diagrams, and optical path diagrams, which can make complicated physical problems visual and simplistic. 1 Sketch the motion process and find the geometric relationship. Example 1 As shown in Figure 1, a positively charged proton is injected perpendicularly from point O at a velocity of v0. There is a uniform magnetic field between the two plates perpendicular to the inside of the paper. The distance between the two plates is known as d. d