Potential energy is a type of mechanical energy that is associated with the relationship between a body and an external (if the object is located in the field) or internal (if the field is inside the object) field or system of forces. It is that is, it can be immediately transformed into other forms of energy , such as kinetic energy, for example.
It of a system, whatever its origin, represents the energy “stored” in it given its configuration or position and, therefore, to measure it, a reference point or configuration must be taken into account.
The concept is useful for both conservative (tending to preserve energy) and dissipative (tending to lose energy) physical systems. The potential energy and the kinetic energy of a system constitute its mechanical energy :
Potential energy + kinetic energy = total mechanical energy
This type of energy is studied not only by classical mechanics, but also by relativistic mechanics and quantum physics (which applies it to particle systems ) . It is classified according to the forces that give rise to it, such as gravitational, elastic, chemical, among others.
Gravitational Potential Energy
It consists of the energy of the object that is under the influence of a gravitational field . This type is measured through the work done by the body’s weight in going from a starting position to a final position.
For example, when picking up a ball and raising it to a certain height from the ground, at this highest point the object reaches the apex of its potential energy (energy that is stored). When the ball is released and begins to fall (attracted by gravitational force), it previously stored is transformed into kinetic energy, while the sphere gains momentum.
The formula for gravitational energy is: EPg = mgh.
m = weight
g = force of gravity
h = height
Elastic Potential Energy
Based on the mechanical force, it is that which is stored from the deformation of a spring or rubber band , for example.
This deformation, when released, can generate a movement that will boost a certain body.
For example, an arrow when placed on a bow. When the line that supports the projectile is pulled back, it is charged with it, from the moment the line is released, the energy is transmitted to the moving arrow.
The formula for elastic potential energy is: EPe = kx2/2.
k = spring force constant
x = length of spring force (measurement of strain)
chemical potential energy
It is the energy stored in the chemical bonds of atoms and molecules . An example is glucose in our body, which stores chemical potential energy that our body (through a process called metabolism ) transforms into heat energy to maintain body temperature .
The same is true of the fossil fuel (hydrocarbons) in the gas tank of a car. It stored in the chemical bonds of the gasoline is converted into mechanical energy to drive the vehicle.
electrostatic potential energy
In electricity, the concept is also applied, which can be converted into other forms of energy, such as kinetic, thermal or light energy , given the enormous versatility of electromagnetism .
In this case, the energy results from the field of electrical forces produced by the charged particles .