Final answer:
Gravitational potential energy is the energy stored in the gravitational field due to an object's position relative to a reference point; it reflects the work done to change an object's position, and it is measured in Joules.
Step-by-step explanation:
The potential energy stored in the gravitational fields of interacting bodies is called gravitational potential energy. This is a property of a system rather than of a single object, due to its physical position. An object in a gravitational field, like that of Earth, gains potential energy relative to a reference point, which is often arbitrarily chosen as Earth's surface, although it is the difference in potential energy that is crucial for work-related calculations. The force applied to the object from outside the system that does positive work increases the gravitational potential energy of the Earth-object system. The unit for this energy is Joule.
Gravitational potential energy can be seen in many common situations, such as a ball being lifted higher off the ground or a roller coaster car at the top of a hill. Despite potential energy being a measure of 'stored' energy, it directly relates to the work done; for example, climbing a ladder requires work against gravity, which in turn increases the gravitational potential energy at a higher rung.