电学实验中的“五会”和“四防止”■郭改凤一、会设计电路图是实验中电路连接的依据，如果没有电路图，就应根据实验的要求，设计出实验电路，并画出电路图，再根据电流的方向在电路图中标出电源的正、负极和电表的正、负接线柱的符号。二、会连接连接电路前要先检查实物... “Five” and “Four Preventions” in Electrical Experiments ■Guo Gaifeng 1、The circuit diagram will be designed based on the circuit connection in the experiment. If there is no circuit diagram, the experimental circuit should be designed according to the requirements of the experiment, and the circuit diagram should be drawn. According to the direction of the current in the circuit diagram, indicate the positive and negative poles of the power supply and the symbols of the positive and negative terminals of the meter. Second, will check the physical before connecting the connection circuit...