动能定理是高中物理的一个重要定理,也是高考的一个热点。它既适用于直线运动,也适用于曲线运动;既适用于恒力做功,也适用于变力做功;力做功可以是连续的,也可以是不连续的;物体受力可以与速度共线,也可以不共线。所以,在解决力学问题时,如不涉及求加速度,应优先考虑应用动能定理。因此,教师在物理教学中,要引导学生灵活应用动能定理解题,从而突破难点问题。一、当物体所受的力中有变力做功时,学生不会 Kinetic theorem is an important theorem of high school physics, but also a hot spot for college entrance examination. It applies not only to linear motion but also to curvilinear motion. It applies not only to constant force but also to variable force to do work. Force can work continuously or discontinuously. Force of object can be collinear with speed, Can not be collinear. Therefore, in solving mechanics problems, if it is not involved in seeking acceleration, priority should be given to the application of kinetic energy theorem. Therefore, teachers in physics teaching, to guide students to apply kinetic energy theorem to solve problems, thus breaking the difficult issues. First, when the force suffered by an object has a variable force, the student does not