In the vast universe of physics and science, potential energy manifests itself in various forms, each with its own characteristics and applications. These forms of potential energy are fundamental to understanding how the world around us works, from the flight of a bird to the operation of power plants.
In this exploration of types of potential energy, we will examine the general characteristics of this classification in a variety of contexts, from the gravitational influence on objects to the magnetic force underlying electronic devices.
Each type of potential energy has its properties and its own relevance in our daily lives, and together, they offer a more complete vision of the incredible world of energy in all its forms.
Gravitational potential energy
Gravitational potential energy is the potential energy that an object gains due to the gravitational effect of another object (generally very large bodies such as the Earth).
This energy is directly proportional to the mass of the object and the size of the attracted mass. The magnitude of the mass attracted creates the acceleration of gravity. This acceleration for the Earth is approximately 9.8 m/s² at the Earth's surface.
Gravitational potential energy is equivalent to the energy necessary to place an object at a certain height.
It is called gravitational energy or potential gravitational energy. For an object with mass m, at height h, the following expression applies to the gravitational energy of the object:
E p = m·g·h
Where (in SI units):
- E p - The potential energy in joules (J).
- m - the mass in kilograms (kg)
- h - the height in meters (m)
- g - the acceleration of fall in m / s² (approximately 9.81 m / s²)
The gravitational potential energy if the object is at the level h = 0 is set to zero.
However, when this object is located at a large distance from the Earth's surface, gravity is no longer constant and the above formula no longer applies.
The expression for the potential gravitational energy then becomes:
The potential energy at an infinite distance from the Earth is zero here, because the formula is the simplest (this is because, unlike many other cases, the energy difference here has a finite limit). The potential energy is therefore always negative, and as in the model mentioned above, it increases as the object moves further away from the earth.
An example of this type is a roller coaster. The moment the car is at the highest point is when it has the most potential energy and hardly any kinetic energy.
The force of gravity exerts a force that pushes the car down. During the descent, the energy is transformed into kinetic energy.
At the lowest points, the kinetic and potential energies have reversed.
Elastic potential energy
Elastic potential energy is the energy stored in the ability of a body to return to its natural position. This form of energy is also called spring energy or elastic potential energy.
Elasticity is a property of certain materials by which, once deformed, stretched or separated from their initial position, they can recover their original state, or equilibrium.
An (ideal) linear spring with spring constant k that is pulled (or pushed) a distance Δl has an increase in spring energy of:
Electrical potential energy
Electrical potential energy is potential energy that results from conservative Coulomb forces. This energy is associated with the configuration of various point charges in a defined system.
It can also be called electrostatic potential energy.
An object can have electrical potential energy due to two main elements: its own electrical charge and its position relative to other electrically charged objects.
Chemical potential energy
Chemical bonds are capable of storing potential energy. Chemical potential energy is related to the structural arrangement of atoms or molecules. This arrangement may be the result of chemical bonds within a molecule or otherwise.
Chemical energy can be transformed into other forms of energy through a chemical reaction.
Examples of chemical potential energy:
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When fuel is burned, chemical energy is converted into heat
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During the metabolic process of digestion. Foods metabolized in a biological organism are transformed into energy.
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The process of photosynthesis. Through this process, green plants transform solar energy into chemical energy.
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Electrochemical reactions. Electrical energy can be converted to chemical energy through electrochemical reactions. These reactions occur during battery charging.
Nuclear potential energy
Nuclear potential energy is a form of energy that is stored in the nuclei of atoms. It is based on the attractive forces that hold together the subatomic components, called nucleons, that make up the nucleus.
This energy is released or absorbed during nuclear reactions, such as fusion and nuclear fission.
- During nuclear fission, a heavy nucleus splits into lighter nuclei, releasing a large amount of energy in the form of heat and radiation.
- On the other hand, in nuclear fusion, light nuclei combine to form a heavier one, releasing even more energy.
Nuclear potential energy is the force behind the immense amount of energy released into the sun and is a key component in the generation of electricity in nuclear power plants.
The study and control of potential nuclear energy has both peaceful and military applications. In peaceful applications, it is used in nuclear power generation for the production of electricity. However, the uncontrolled release of this energy in the form of nuclear weapons can have catastrophic consequences.
Magnetic potential energy
Magnetic potential energy relates to the energy stored in a magnetic field. Magnets and coils of wire carrying electrical current are examples of systems that can contain this form of energy.
When we move a magnet or alter the current in a coil, the magnetic potential energy is transformed into kinetic or electrical energy, just as occurs in electrical generators.
Thermal potential energy
Thermal potential energy refers to the energy stored in the temperature of a system. In this context, the higher temperature of an object or substance is associated with a greater potential thermal energy.
This energy can be harnessed to perform useful work in heat engine applications, such as internal combustion engines or steam turbines. When heat is transferred from one system to another, thermal potential energy can be converted into mechanical work, electricity, or any other form of useful energy depending on the application, making it an essential component in power generation and in various areas. of technology.
Quantum Well Potential Energy
Quantum well potential energy is an essential concept in quantum physics and relates to the energy stored by subatomic particles confined in microscopic structures called "quantum wells."
These quantum wells are like particle traps, where particles are kept within well-defined boundaries.
Potential energy of torsional spring
In mechanical systems involving torsional springs (springs that twist rather than stretch or compress), torsional potential energy is stored.
This potential energy is released when the torsional spring relaxes and returns to its equilibrium position. This form of energy has applications in devices such as watches and torque measurement tools.