The properties and characteristics of the electric field are studied by almost all technical specialists. But a university course is often written in complex and incomprehensible language. Therefore, within the framework of the article, the characteristics of electric fields will be described in an accessible way so that every person can understand them. In addition, we will pay special attention to interrelated concepts (superposition) and the possibilities for the development of this area of physics.
General information
According to modern concepts, electric charges do not interact directly with each other. An interesting feature emerges from this. So, each charged body has its own electric field in the surrounding space. It affects other entities. The characteristics of electric fields are of interest to us because they show the effect of the field on electric charges and the force with which it is carried out. What conclusion can be drawn from this? Charged bodies do not have a mutual direct effect. For this, electric fields are used. How can they be explored? To do this, you can use a test charge - a small point particle beam, which is notwill have a significant impact on the existing structure. So what are the characteristics of the electric field? There are three of them: tension, tension and potential. Each of them has its own characteristics and spheres of influence on the particles.
Electric field: what is it?
But before moving on to the main subject of the article, you need to have a certain amount of knowledge. If they are, then this part can be safely skipped. First, let's consider the question of the reason for the existence of an electric field. In order for it to be, a charge is needed. Moreover, the properties of the space in which the charged body resides should differ from those where it does not exist. There is such a feature here: if a charge is placed in a certain coordinate system, then changes will not occur instantly, but only at a certain speed. They will, like waves, spread through space. This will be accompanied by the appearance of mechanical forces that act on other carriers in this coordinate system. And here we come to the main thing! The emerging forces are not the result of direct influence, but of interaction through an environment that has changed qualitatively. The space in which such changes occur is called the electric field.
Features
A charge located in an electric field moves in the direction of the force that acts on it. Is it possible to achieve a state of rest? Yes, it's quite real. But for this, the strength of the electric field must be balanced by someother influence. As soon as the imbalance occurs, the charge starts moving again. The direction in this case will depend on the greater force. Although if there are a lot of them, the end result will be something balanced and universal. To better imagine what you have to work with, lines of force are depicted. Their directions correspond to the acting forces. It should be noted that lines of force have both a beginning and an end. In other words, they do not close on themselves. They begin on positively charged bodies, and end on negative ones. This is not all, in more detail about the lines of force, their theoretical background and practical implementation, we will talk a little further in the text and consider them together with Coulomb's law.
Electric field strength
This characteristic is used to quantify the electric field. This is quite difficult to understand. This characteristic of the electric field (strength) is a physical quantity equal to the ratio of the force of action on a positive test charge, which is located at a certain point in space, to its value. There is one special aspect here. This physical quantity is a vector. Its direction coincides with the direction of the force that acts on the positive test charge. You should also answer one very common question and note that the strength characteristic of the electric field is exactly the intensity. And what happens to immobile and unchanging subjects? Their electric field is considered electrostatic. When working with a point charge andinterest in the study of tension is provided by lines of force and Coulomb's law. What features exist here?
Coulomb's Law and lines of force
The force characteristic of the electric field in this case works only for a point charge, which is located at a distance of a certain radius from it. And if we take this value modulo, then we will have a Coulomb field. In it, the direction of the vector directly depends on the sign of the charge. So, if it is positive, then the field will "move" along the radius. In the opposite situation, the vector will be directed directly to the charge itself. For a visual understanding of what is happening and how, you can find and familiarize yourself with the drawings depicting the lines of force. The main characteristics of the electric field in textbooks, although rather difficult to explain, but the drawings, they should be given their due, they are of high quality. True, one should note such a feature of books: when constructing drawings of force lines, their density is proportional to the modulus of the tension vector. This is a small hint that can be of great help in the knowledge control or exam.
Potential
The charge always moves when there is no balance of forces. This tells us that in this case the electric field has potential energy. In other words, it can do some work. Let's look at a small example. An electric field has moved a charge from a pointAnd in B. As a result, there is a decrease in the potential energy of the field. It happens because the work has been done. This power characteristic of the electric field will not change if the movement was made under outside influence. In this case, the potential energy will not decrease, but increase. Moreover, this physical characteristic of the electric field will change in direct proportion to the applied external force, which moved the charge in the electric field. It should be noted that in this case all the work done will be spent on increasing the potential energy. To understand the topic, let's take the following example. So we have a positive charge. It is located outside the electric field that is being considered. Due to this, the impact is so small that it can be ignored. An external force arises, which introduces a charge into the electric field. She does the work necessary to move. In this case, the forces of the field are overcome. Thus, an action potential arises, but already in the electric field itself. It should be noted that this may be a heterogeneous indicator. So, the energy that relates to each specific unit of positive charge is called the potential of the field at that point. It is numerically equal to the work that was done by an external force to move the subject to a given place. The field potential is measured in volts.
Voltage
In any electric field, one can observe how positive charges "migrate" from points with a high potential to those that have low values of this parameter. Negatives follow this path in the opposite direction. But in both cases this happens only due to the presence of potential energy. The voltage is calculated from it. To do this, it is necessary to know the value by which the potential energy of the field has become smaller. The voltage is numerically equal to the work that was done to transfer a positive charge between two specific points. An interesting correspondence can be seen from this. So, voltage and potential difference in this case are the same physical entity.
Superposition of electric fields
So, we have considered the main characteristics of the electric field. But in order to better understand the topic, we propose to additionally consider a number of parameters that may be important. And we'll start with a superposition of electric fields. Previously, we considered situations in which there was only one specific charge. But there are a lot of them in the fields! Therefore, considering a situation close to reality, let's imagine that we have several charges. Then it turns out that forces that obey the rule of vector addition will act on the trial subject. Also, the principle of superposition says that a complex movement can be divided into two or more simple ones. It is impossible to develop a realistic motion model without taking superposition into account. In other words, the particle we are considering under existing conditions is affected by various charges, each of which has its ownelectric field.
Use
It should be noted that now the possibilities of the electric field are not being used to their full potential. Even, it would be more correct to say, its potential is hardly used by us. Chizhevsky's chandelier can be cited as a practical implementation of the possibilities of the electric field. Earlier, in the middle of the last century, mankind began to explore space. But scientists had many unresolved questions. One of them is air and its harmful components. The Soviet scientist Chizhevsky, who at the same time was interested in the energy characteristic of the electric field, took up the solution of this problem. And it should be noted that he got a really good development. This device was based on the technique of creating aeroionic air flows due to small discharges. But within the framework of the article, we are interested not so much in the device itself, as in the principle of its operation. The fact is that for the functioning of the Chizhevsky chandelier, not a stationary power source was used, but an electric field! Special capacitors were used to concentrate the energy. The energy characteristic of the electric field of the environment significantly influenced the success of the device. That is, this device was developed specifically for spacecraft, which are literally crammed with electronics. It was powered by the results of the activities of other devices connected to constant power sources. It should be noted that the direction was not abandoned, and the possibility of taking energy from the electric field is being investigated now. Truth,It should be noted that significant progress has not yet been achieved. It is also necessary to note the relatively small scale of the ongoing research, and the fact that most of them are carried out by volunteer inventors.
What are the characteristics of electric fields affected by?
Why study them? As mentioned earlier, the characteristics of an electric field are strength, voltage and potential. In the life of an ordinary ordinary person, these parameters cannot boast of significant influence. But when questions arise that something large and complex should be done, then not considering them is a luxury. The fact is that an excessive number of electronic fields (or their excessive strength) leads to interference in the transmission of signals by equipment. This leads to distortion of the transmitted information. It should be noted that this is not the only problem of this type. In addition to the white noise of technology, excessively strong electronic fields can also negatively affect the functioning of the human body. It should be noted that a small ionization of the room is still considered a blessing, since it contributes to the deposition of dust on the surfaces of a human dwelling. But if you look at how many all kinds of equipment (refrigerators, TVs, boilers, telephones, power systems, and so on) are in our homes, we can conclude that, alas, this is not good for our he alth. It should be noted that the low characteristics of electric fields do almost no harm to us, since toHumanity has long been accustomed to cosmic radiation. But it's hard to say about electronics. Of course, it will not be possible to refuse all this, but it is possible to successfully minimize the negative impact of electric fields on the human body. For this, by the way, it is enough to apply the principles of energy efficient use of technology, which provide for minimizing the operating time of mechanisms.
Conclusion
We examined what physical quantity is a characteristic of the electric field, where what is used, what is the potential of developments and their application in everyday life. But still I would like to add a few final words about the topic. It should be noted that quite a large number of people were interested in them. One of the most visible traces in history was left by the famous Serbian inventor Nikola Tesla. In this, he managed to achieve considerable success regarding the implementation of his plans, but, alas, not in terms of energy efficiency. Therefore, if there is a desire to work in this direction, there are a lot of undiscovered opportunities.
