初中物理是学生学习困难较大的学科之一。帮助学生掌握概念是教学的核心问题。定义性概念是初中物理基本概念的主要类型。教学的主要困难是由感性经验到理性认识之间的转化。然而具体与抽象的结合，正是投影教材的特点之一。如何使用好投影教材，克服初中物理概念教学的困... Junior high school physics is one of the subjects that students have more difficulties in learning. Helping students grasp the concept is the core issue of teaching. The concept of definition is the main type of basic concept of junior high school physics. The main difficulty in teaching is the transformation from perceptual experience to rational understanding. However, the combination of specific and abstract, it is one of the characteristics of projection materials. How to use projection material, to overcome the junior middle school physics concept of sleepy ...