“密度”是初中物理的重点内容之一,它在今后学习液体压强、浮力以及高中气态方程等方面都有广泛应用。同时,“密度”对于刚学物理的初二学生来说,又是一个比较抽象、比较难懂的概念,历届都有相当一些学生由于对此概念弄不清楚,影响以后有关内容的学习。为了使学生更好地理解掌握密度概念,我们在教 “Density” is one of the key contents of junior high school physics. It is widely used in the future to learn liquid pressure, buoyancy, and high school gaseous equations. At the same time, “density” is a relatively abstract and difficult concept for the second-year students who just studied physics. In the past, quite a number of students have not understood the concept and have influenced the study of related contents. . In order to enable students to better understand the concept of density, we are teaching