功的概念是了解能的概念的基础。中学学生对于能的了解所感受的困难有很多是由于对功的了解不够明确而起的,因此功的概念的讲解是很重要的。如果功的物理意义及其量度法则讲得清楚学生在深切体会之后,对于能的概念就感到容易了解了。一般说来,中学学生对于功的量度并不感到严重困难,即使对于功的概念没有了解得深切,也能按照公式解题,而且解得不错。但若要求他们把功的物理意义说得正确,那就是很困难的了。他们的缺点表现在这样一些解答中:他们举出许多散碎的事例企图代替功的解释,例 The concept of work is the basis for understanding the concept of energy. Many of the difficulties experienced by middle school students in understanding their energy are due to the lack of clear understanding of their work. Therefore, it is important to explain the concept of work. If the physical meaning of the work and its measure of law makes it clear that after the students have fully realized the concept of energy, they feel easy to understand. Generally speaking, secondary school students did not feel any serious difficulty in measuring their work. Even if they did not understand the concept of work, they could solve the problem according to the formula and did well. But it is very difficult to ask them to correct the physical meaning of the work. Their shortcomings are manifested in the following solutions: They cite many instances of splinter attempts to replace the explanation of work, for example