一、知识网络二、复习指导（一）机械能1．能的概念一个物体能够做功，我们就说它具有能量．注能是抬物体做功的本领与实际做功是不同的．物体能够做的功越大，具有的能量越大．2．动能物体由于运动而具有的能叫动能，其大小田物体质量和速度大小决定．3．势能物体由于被举高而 First, knowledge network two, review guidance (a) mechanical energy 1. The concept of energy. An object can do work. We say it has energy. Note that the ability to lift objects to do work is different from actual work. The more work an object can do, the more energy it has. 2. The kinetic energy of a kinetic energy object can be called kinetic energy, which is determined by the mass and velocity of the field object. 3. Potential energy objects are raised