Gravitational Energy, Potential Energy
It is important to know the two main types of potential energy: gravitational potential energy and elastic potential energy
Every object may have Potential energy but Gravitational Potential energy is only stored in the height of the object. Any time that a heavy object is kept high up, a force or power is likely to be holding it up there. This is the reason why it stays up and does not fall. It is important to note that the heavier the object, the more its potential energy.
the diagram below:
Consider Mr Green throwing a bag of gold coins to Mr Red, who is up a tower. As Mr Green throws the bag from A to B, potential energy is transferred from Mr Green into the bag, which now has kinetic energy.
As the bag moves upwards, kinetic energy decreases, and gravitational energy increases. At the highest point (B) Kinetic energy is zero, and Gravitational potential energy is highest.
As the bag did not get to Mr Red, it starts falling from point B downwards due to gravity. It starts falling slowly (kinetic energy is low) and then speeds up downwards.
At point A, the bag is at full speed and kinetic energy is highest, whiles gravitational energy is nearly lost.
When the bag of gold coins hits the ground, kinetic energy is converted into heat and sound by the impact.
It is worth noting that the higher the gravitational energy of an object moving downwards, the lower the kinetic energy, and the lower the kinetic energy of an object moving upwards, the higher its gravitational energy.