Describe what happens to the KE of the simple pendulum as it swings back and forth.

As the pendulum swings back and forth, the balance between the two types of energy changes constantly. At some points in its swing, the pendulum has more kinetic energy. At other points, it has more potential energy. Of course, no working system is ideal. pendulum is an object hung from a fixed point that swings back and forth under the action of gravity. ... When the swing is raised and released, it will move freely back and forth due to the force of gravity on it. As a pendulum swings, its potential energy converts to kinetic and back to potential. Recall the concept of conservation of energy—that energy may change its form, but have no net change to the amount of energy.
Answer. When you let go of the raised bob, its potential energy is converted to kinetic energy as it swings down with increasing speed, and then back to potential energy as it swings up on the other side with decreasing speed. The massive object is affectionately referred to as the pendulum bob. When the bob is displaced from equilibrium and then released, it begins its back and forth vibration about its fixed equilibrium position. The motion is regular and repeating, an example of periodic motion.