正确识别电路的连接方式,是解答电学问题的先决条件.采用“节点法”画等效电路,是识别电路的最佳方法之一. “节点法”就是不管导线有多长,只要该导线上没有电源、用电器等,导线两端就可以看成一个“节点”,找出各用电器两端的公共“节点”,再把各用电器画在对应的两节点之间,即可得到易于识别的等效电路图. Correctly identifying the connection of the circuit is a prerequisite for solving the electrical problem. Using the “node method” to draw the equivalent circuit is one of the best ways to identify the circuit. The “node method” means that no matter how long the wire is, only Without power supply, electrical appliances, etc., both ends of the wire can be regarded as a “node”, find the common “node” at each end of each appliance, and then draw each appliance between the corresponding two nodes, and it can be easily identified. The equivalent circuit diagram.