what is conservation of mechanical energy

• We know that the mechanical energy is sum of kinetic energy and potential energy.
• The principle of conservation of energy states that the total mechanical energy in the system remains constant as long as the forces acting on the system are conservative. This means that the potential energy of an object can get completely transformed to the kinetic energy and vice-versa.
• For example- When a ball is at height it possesses potential energy and when it is dropped down the potential energy transforms to kinetic energy and when a ball is at half a distance away from the ground the potential energy is equal to kinetic energy and when the ball reaches the ground the potetial energy gets completely transformed to the kinetic energy. Which means when the ball reaches the ground the potential energy is equal to zero and kinetic energy is maximum. Hence, the falling of an object from a height to the ground is also an example of conservation of mechanical energy where the air resistance is considered to be negligible.
• Similarly, oscillation of simple pendulum is also an example of conservation of mechanical energy.