在初中物理课本“防止雷电”一节内容中,课本中只简要介绍了避雷针:把针状金属放在建筑物的顶部,再用一根很粗的金属丝接入大地。每当教师在讲解这部分内容时,学生往往会问,为什么指向空中的金属要做成针状?对此,教师往往用一句“尖端易放电”敷衍过去。结果学生既不知道“尖端易放电”的原理,也没有看到“尖端易放电”的现象,给教学带来了遗憾。为此,我设计了一个简单易行的尖端放电实验装置。取起电感应机一台,自制一个金属小钢叉,两叉的一叉为尖端,另一叉为平端,把钢叉的柄用导线接在起电感 In the textbook “Thunderbolt Prevention” in the junior high school physics textbook, the textbook contains a brief description of the lightning rod: put the needle metal on the top of the building and connect it to the earth with a very thick wire. Whenever teachers explain this part of the content, students often ask why the metal in the air needs to be acicular. To this end, teachers often use the word “sophisticated discharge” in the past. As a result, students did not know the principle of “cutting edge and discharging easily” and did not see the phenomenon of “cutting edge and discharging easily”, which brought regret to teaching. To this end, I designed an easy-to-experiment tip discharge device. Pick up a induction machine, a small metal self-made fork, a fork for the tip of the fork, the other fork is flat, the handle of the fork connected with a wire inductance