Answer:
Step-by-step explanation:
Because the kinetic and potential energy are constant. A good example of kinetic and potential energy are throwing a ball up. It leaves your hand with kinetic energy. When it reaches the top it doesn’t have any kinetic force but potential energy equal to the kinetic energy the ball had when you threw it up. And, when it comes back to your hand it has the same kinetic energy it had when it left your hand. Thus, the sum of the kinetic energy plus potential energy is a constant.