Potential energy is stored energy.
Potential energy can be thought of as energy stored within a physical system.
This energy can be released or converted into other forms of energy, including kinetic energy.
It is called potential energy because it has the potential to change the states of objects in the system when the energy is released.
Potential energy is the energy that is stored.
Potential energy exists when there is a force that tends to pull an object back towards some original position when the object is displaced.
This force is often called a restoring force. The phrase 'potential energy' was coined by William Rankine.
For example, when a spring is stretched to the left, it exerts a force to the right so as to return to its original, un-stretched position.
Or, suppose that a weight is lifted straight up. The force of gravity will try to bring it back down to its original position.
The initial steps of stretching the spring and lifting the weight both require energy to perform.
According to the principle of conservation of energy, energy cannot be created or destroyed;
hence this energy cannot disappear. Instead it is stored as potential energy.
If the spring is released or the weight is dropped, this stored energy will be converted into kinetic energy by the restoring force —
elasticity in the case of the spring, and gravity in the case of the weight.
The more formal definition is that potential energy is the energy of position, that is,
the energy an object is considered to have due to its position in space.
There are a number of different types of potential energy, each associated with a particular type of force.
More specifically, every conservative force gives rise to potential energy.
For example, the work of elastic force is called elastic potential energy;
Work of gravitational force is called gravitational potential energy,
Work of the Coulomb force is called electric potential energy;
work of strong nuclear force or weak nuclear force acting on the baryon charge is called nuclear potential energy;
work of intermolecular forces is called intermolecular potential energy.
Chemical potential energy, such as the energy stored in fossil fuels,
is the work of Coulomb force during rearrangement of mutual positions of electrons and nuclei in atoms and molecules.
Thermal energy usually has two components: the kinetic energy of random motion of particles and potential energy of their mutual positions.
Potential energy is the energy that exists by virtue of the relative positions (configurations) of the objects within a physical system.
This form of energy has the potential to change the state of other objects around it, for example, the configuration or motion.
Various forms of energy can be grouped as potential energy.
Each of these forms is associated with a particular kind of force acting in conjunction with some physical property of matter (such as mass, charge, elasticity, temperature etc).
For example,
Gravitational potential energy is associated with the gravitational force acting on object's mass;
Elastic potential energy with the elastic force (ultimately electromagnetic force) acting on the elasticity of a deformed object;
Electrical potential energy with the coulombic force;
Strong nuclear force or weak nuclear force acting on the electric charge on the object;
Chemical potential energy, with the chemical potential of a particular atomic or molecular configuration acting on the atomic/molecular structure of the chemical substance that constitutes the object;
Thermal potential energy with the electromagnetic force in conjunction with the temperature of the object.
For an example of gravitational potential energy, consider a book placed on top of a table.
To raise the book from the floor to the table, work must be done, and energy supplied.
(If the book is lifted by a person then this is provided by the chemical energy obtained from that person's food and then stored in the chemicals of the body.)
Assuming perfect efficiency (no energy losses), the energy supplied to lift the book is exactly the same as the increase in the book's gravitational potential energy.
The book's potential energy can be released by knocking it off the table.
As the book falls, its potential energy is converted to kinetic energy.
When the book hits the floor this kinetic energy is converted into heat and sound by the impact..