所谓等效替代法就是将一个复杂的研究对象或复杂的物理过程在对所研究问题等效的前提下,用一简单明了的对象或过程取而代之。中学物理中如力的合成与分解、串并联电阻的等效电阻、串并联电容器的等效电容、交流电的有效值等均包含有等效替代法的运用。同时需要指出,等效替代法也是中学物理解题中常用的一种方法,尤其是一些若从正面分析求解时演算冗长、计算繁杂或 The so-called equivalent substitution method is to replace a complex object or process with a simple object or process under the premise of equivalent research. The composition and disassembly of high school physics such as force, the equivalent resistance of series and parallel resistors, the equivalent capacitance of series and shunt capacitors, the effective value of AC and so on, all include the use of equivalent substitution method. At the same time, it should be pointed out that the equivalent substitution method is also a commonly used method in solving problems of physics in middle schools. In particular, some methods that are lengthy, complicated to calculate or