高中物理有多种求变力功方法,如用W=Pt、动能定理W=ΔE_k、平均值法、等效法、微元法、图像法、功能关系等。笔者在应对奥赛中,借助于这些方法迅速解决了问题。一、平均值法若物体受到的力的方向不变,而大小随位移成线性变化,即力均匀变化时,用平均力求变力功。例1如图1,在航天飞船上有一长度L=20cm High school physics there are a variety of variable power methods, such as the use of W = Pt, kinetic energy theorem W = ΔE_k, mean value method, equivalent method, micro element method, image method, functional relationship. In response to the Orsay, the author quickly solved the problem with these methods. First, the average method If the direction of force by the same object, while the size of the linear change with the displacement, that is, uniform force changes, with the average force to change. Example 1 In Figure 1, there is a length L = 20 cm on the spacecraft