一、教材分析电功公式是掌握层次之一,又是第九章的开首篇,足见这节的重要性.在力学中,物体做功必须具备两个必要因素.而在电学中,不但物体在电磁力作用下移动算做功,电流通过用电器使其发热、发光、发声等现象都是电流做功的表现.这就扩展了力学中功的概念, First, the analysis of teaching materials is one of the levels of mastering the electric power formula, and it is also the first chapter of the ninth chapter. This shows the importance of this section. In mechanics, the work of an object must have two necessary factors. In electronics, not only the object Under the action of electromagnetic force, mobile work is performed, and the current through the use of electrical appliances causes the phenomena of heat generation, light emission, and vocalization to be the performance of current work. This expands the concept of mechanical work,