滑动变阻器是依靠改变电路中电阻丝的长度来改变电阻的大小,从而改变电流强度和电医的仪器。在教学中,必须让学生在掌握决定电阻大小的因素的基础上,弄懂电路中电阻丝的长短和电阻的大小以及电流强度、电压的关系。由于涉及的物理量较多,知识面较广,学生感到难以理解(因此,滑动变阻器是变阻器这节内容的难点)。为了解决这一难点,我们在教法上作了如下探讨。一、打好甚础新旧衔接为了学好滑动变阻器的有关知识,我们在教学“决定电阻大小的因素”这节课时,加深了电阻的大小跟导体的长度成正比,跟导体的横截面积成反 Sliding varistors rely on changing the length of the resistance wire in the circuit to change the size of the resistance, thereby changing the current intensity and electromedical instruments. In teaching, students must understand the factors that determine the size of the resistance, and understand the length of the resistance wire in the circuit, the size of the resistance, and the relationship between the current intensity and the voltage. Due to the large number of physical quantities involved and the wide range of knowledge, students find it difficult to understand (thus, the sliding rheostat is a difficult part of the varistor section). In order to solve this difficulty, we made the following discussion on the teaching method. First, to lay a good foundation for the old and new convergence In order to learn the knowledge of the sliding rheostat, we in teaching “determine the size of the resistance factor ” this class, deepened the size of the resistance is proportional to the length of the conductor, with the conductor’s cross-sectional area Inverse