Gravitational potential energy is the energy an object possesses due to its position in a gravitational field. The formula for gravitational potential energy is $U = mgh$, where $m$ is the mass of the object, $g$ is the acceleration due to gravity, and $h$ is the height of the object above a reference point.

Elastic potential energy is the energy an object possesses due to its deformation. The formula for elastic potential energy is $U = rac{1}{2}kx^2$, where $k$ is the spring constant and $x$ is the displacement of the object from its equilibrium position.

Chemical potential energy is the energy an object possesses due to its chemical composition. The formula for chemical potential energy is $U = -rac{k}{r}$, where $k$ is a constant and $r$ is the distance between the particles.

Gravitational potential energy is the energy an object possesses due to its position in a gravitational field. A book resting on a table is an example of gravitational potential energy because it has the potential to fall and release its energy.

Elastic potential energy is the energy an object possesses due to its deformation. A stretched rubber band is an example of elastic potential energy because it has the potential to release its energy when it is released.

Chemical potential energy is the energy an object possesses due to its chemical composition. A battery is an example of chemical potential energy because it has the potential to release its energy through chemical reactions.

The SI unit of potential energy is Joule (J). It is the energy required to move an object one meter against a force of one Newton.

Potential energy and kinetic energy are inversely proportional to each other. As the potential energy of an object increases, its kinetic energy decreases, and vice versa.

The principle of conservation of energy states that energy can be transferred from one form to another, but it cannot be created or destroyed. This means that the total amount of energy in a closed system remains constant.

The potential energy of an object at rest on the ground is zero. This is because the object has no height above a reference point, and therefore no gravitational potential energy.

The potential energy of an object at a height $h$ above the ground is $U = mgh$, where $m$ is the mass of the object, $g$ is the acceleration due to gravity, and $h$ is the height of the object above a reference point.

The potential energy of a stretched spring is $U = rac{1}{2}kx^2$, where $k$ is the spring constant and $x$ is the displacement of the object from its equilibrium position.

The potential energy of a chemical reaction is $U = -rac{k}{r}$, where $k$ is a constant and $r$ is the distance between the particles.

The potential energy of a flowing river is $U = mgh$, where $m$ is the mass of the water, $g$ is the acceleration due to gravity, and $h$ is the height of the water above a reference point.

The potential energy of a battery is $U = -rac{k}{r}$, where $k$ is a constant and $r$ is the distance between the particles.