Conversion of Potential Energy into Kinetic Energy
Potential energy is the energy stored in an object due to its position or state. When an object is lifted to a certain height above the ground, it gains potential energy. This potential energy can be converted into kinetic energy when the object is allowed to fall freely.

Law of Conservation of Energy
According to the law of conservation of energy, energy cannot be created or destroyed, only transformed from one form to another. In the case of potential and kinetic energy, the total energy of the system remains constant.

Gravitational Potential Energy
When an object is lifted to a certain height above the ground, it gains gravitational potential energy. This energy is converted into kinetic energy as the object falls back to the ground. The potential energy is gradually transformed into kinetic energy as the object accelerates due to gravity.

Example: Pendulum Swing
A pendulum is another example where potential energy is converted into kinetic energy. At the highest point of its swing, the pendulum has maximum potential energy. As it swings down, this potential energy is converted into kinetic energy. At the lowest point of the swing, the pendulum has maximum kinetic energy.

Conclusion
In summary, potential energy is converted into kinetic energy when an object moves from a higher position to a lower position. This conversion follows the law of conservation of energy, where the total energy of the system remains constant. This transformation of energy is essential for various natural processes and phenomena.