Energy is what makes life existnot only on our planet, but also in the universe. However, it can be very different. So, heat, sound, light, electricity, microwaves, calories are different types of energy. For all the processes occurring around us, this substance is necessary. Most of the energy of all things on Earth receives from the sun, but there are other sources of it. The sun transmits it to our planet as much as 100 million of the most powerful power stations would simultaneously produce.
В теории, выдвинутой Альбертом Эйнштейном, The relationship between matter and energy is being studied. This great scientist was able to prove the ability of one substance to turn into another. It turned out that energy is the most important factor in the existence of bodies, and matter is secondary.
Energy is, by and large, the abilitydo some work. It is she who stands behind the concept of power, capable of moving the body or giving it new properties. What does the term "energy" mean? Physics is a fundamental science to which many scientists from different eras and countries have dedicated their lives. Even Aristotle used the word "energy" to denote human activity. Translated from the Greek language, “energy” is “activity”, “force”, “action”, “power”. The first time this word appeared in the Greek scholar's treatise called “Physics”.
In the generally accepted sense, this term wasintroduced by the English physicist Thomas Jung. This momentous event happened back in 1807. In the 50s of the XIX century. English mechanic William Thomson first used the concept of "kinetic energy", and in 1853 the Scottish physicist William Renkin coined the term "potential energy."
Today, this scalar value is present inall sections of physics. It is a single measure of various forms of motion and interaction of matter. In other words, it is a measure of the transformation of one form into another.
The amount of energy is measured in joules (j). Depending on the type of energy, this special unit may have different designations, for example:
In nature, there are many different types of energy. The main ones are:
There are other types of energy:light, sound, magnetic. In recent years, an increasing number of physicist scientists are inclined to the hypothesis of the existence of so-called "dark" energy. Each of the previously listed types of this substance has its own characteristics. For example, sound energy is capable of being transmitted by waves. They contribute to the emergence of vibrations of the eardrum in the ear of people and animals, through which you can hear sounds. In the course of various chemical reactions, the energy necessary for the vital activity of all organisms is released. Any fuel, food, batteries, batteries are the storage of this energy.
Our star gives the Earth energy in the formelectromagnetic waves. Only in this way can it overcome the vastness of the cosmos. Thanks to modern technology, such as solar panels, we can use it with the greatest effect. Excess unused energy is accumulated in special energy storage facilities. Along with the types of energy listed above, thermal sources, rivers, tides and biofuels are often used.
This kind of energy is studied in the physics section,called "Mechanics." It is denoted by the letter E. Its measurement is carried out in joules (J). What is this energy like? Physics of mechanics studies the motion of bodies and their interaction with each other or with external fields. The energy caused by the movement of bodies is called kinetic (indicated by Ek), and the energy caused by the interaction of bodies or external fields is called potential (En). The sum of movement and interaction is the total mechanical energy of the system.
For the calculation of both types there is a general rule.To determine the magnitude of the energy, it is necessary to calculate the work necessary to transfer the body from the zero state to this state. Moreover, the more work, the more energy the body will have in this state.
There are several types of energy separation.According to various signs, it is divided into: external (kinetic and potential) and internal (mechanical, thermal, electromagnetic, nuclear, gravitational). Electromagnetic energy, in turn, is divided into magnetic and electric, and nuclear energy - into the energy of weak and strong interaction.
Any moving bodies are distinguished by the presence ofkinetic energy. It is often called motive. The energy of the body that moves is lost when it is slowed down. Thus, the faster the speed, the greater the kinetic energy.
When a moving body touches a fixed object, a part of the kinetic is transmitted to the latter, which also sets it in motion. The formula for kinetic energy is as follows:
In words, this formula can be expressed as follows: the kinetic energy of an object is equal to half the product of its mass and the square of its velocity.
This kind of energy is possessed by bodies thatare in any force field. So, the magnetic occurs when the object is under the action of a magnetic field. All bodies on earth have potential gravitational energy.
Depending on the properties of the objects of study, theymay have different types of potential energy. Thus, elastic and elastic bodies that are able to stretch, have the potential energy of elasticity or tension. Any falling body that was previously motionless loses a potential body and acquires a kinetic one. In this case, the magnitude of these two types will be equivalent. In the field of our planet, the potential energy formula will have the following form:
In words, this formula can be expressed as: the potential energy of an object interacting with the Earth is equal to the product of its mass, the acceleration of free fall and the height at which it is located.
This scalar is a characteristicenergy reserves of a material point (body) located in a potential force field and going to acquire kinetic energy due to the work of the field forces. Sometimes it is called the coordinate function, which is a term in the Lagrangian system (the Lagrange function of the dynamical system). This system describes their interaction.
Potential energy is equated to zero forsome configuration of bodies located in space. The choice of configuration is determined by the convenience of further calculations and is called the "normalization of potential energy."
One of the most basic tenets of physicsis the law of conservation of energy. In accordance with it, the energy does not arise from anywhere and does not disappear anywhere. She constantly moves from one form to another. In other words, only a change in energy occurs. For example, the chemical energy of a flashlight battery is converted into electrical energy, and from it into light and heat energy. Various household appliances turn electrical into light, heat or sound. Most often, the end result of a change is heat and light. After that, the energy goes into the surrounding space.
The law of energy can explain manyphysical phenomena. Scientists argue that its total volume in the universe remains constant. No one can create energy again or destroy. Developing one of its types, people use the energy of fuel, falling water, an atom. At the same time, one of its kind turns into another.
In 1918scientists were able to prove that the law of energy conservation is a mathematical consequence of the translational symmetry of time - the magnitude of the conjugate energy. In other words, energy is conserved due to the fact that the laws of physics do not differ at different points in time.
Energy is the ability of the body to do work.In closed physical systems, it is preserved for the entire time (as long as the system is closed) and is one of the three additive integrals of motion, which retain their magnitude as they move. These include: energy, angular momentum, impulse. The introduction of the concept of "energy" is appropriate when the physical system is homogeneous in time.
It is the sum of the molecular energies.interactions and thermal motions of the molecules that make it up. It cannot be measured directly, since it is an unambiguous function of the state of the system. Whenever a system is in a given state, its internal energy has an inherent value, regardless of the history of the system. The change in internal energy in the process of transition from one physical state to another is always equal to the difference between its values in the final and initial states.
In addition to solids, gases also have energy.It represents the kinetic energy of the thermal (chaotic) motion of the particles of the system, which include atoms, molecules, electrons, nuclei. The internal energy of an ideal gas (the mathematical model of a gas) is the sum of the kinetic energies of its particles. This takes into account the number of degrees of freedom, which is the number of independent variables that determine the position of a molecule in space.
Every year, humanity consumes allmore energy. Most often, fossil hydrocarbons such as coal, oil and gas are used to obtain the energy needed for lighting and heating our homes, working vehicles and various mechanisms. They refer to non-renewable resources.
К сожалению, только незначительная часть энергии is mined on our planet by using renewable resources such as water, wind and the sun. To date, their share in the energy sector is only 5%. Another 3% of people receive in the form of nuclear energy produced in nuclear power plants.
Non-renewable resources have the following reserves (in joules):
The annual value of the renewable resources of the Earth:
Only with a timely transition fromuse of non-renewable energy reserves of the Earth to renewable humanity has a chance for a long and happy existence on our planet. To implement advanced developments, scientists around the world continue to carefully study the various properties of energy.
