Electric field

The electric field is any spatial area where the electric charges , which can be positive or negative, are related in a certain space limit, the electric field being both the delimitation of the space in the plane, as well as the space of a body charged with electricity. . It is not measurable in itself, but what is measured is the effect generated by the electrical charges inside it. It is Faraday, who proposed in the year 1832, the idea of ​​the electric field more thoroughly to demonstrate the principle of electromagnetic induction.

Parties

• Magnitude (Intensity): defined as the size of the vector representing the field. A model of particles found within the electric field is used.
• Direction: visualized by an axis that crosses the particles and the point in space that is in interaction.
• Direction: it is determined from the orientation of the line that represents the magnitude that is located on the axis that provides the direction of the electric field.
• Electric field lines or lines of force: they are defined from imaginary lines that are drawn in such a way that their direction at any point is the same as the direction of the field at that point. They move apart in positive electric charges and move closer in negative electric charges.
• Force: the electric force is called the set that exists between the electric charges.

Characteristics of an electric field

Electric fields must have the following characteristics for their proper operation:

• They depend solely on the load that generates it.
• The electric field exists only with the detection of one electric charge , the second or other charges are not necessary for its detection. As it exists even though the load is not in motion.
• Two or more electric charges interact , which can be positive (+) or negative (-). Opposite charges attract and like charges repel.
• Visualizing the lines in the electric field can visualize the magnitude and direction of E.
• The intensity or magnitude of the electric field is measured in volts per meter (v / m) . This decreases as the distance from the source increases.
• The power source is based on electrical voltage .

History

To understand how electricity works during the 18th century, research such as Coulomb’s focuses on the subject of electricity and its internal and external functioning and its handling in everyday use. It was possible to establish that electric charges could interact at the distance between them, as well as masses against gravitational forces . That is, a mass or a load could inexplicably, without any mediator, notice the presence of another in their surroundings.

For his part, Faraday proposes an alternative interpretation , which will be very useful , contributing to the idea of ​​the electric field, the proposal that: the space surrounding an electric charge is affected by its presence, since she modifies her characteristics. In one of his attempts to test his approach, Faraday describes it as invisible tentacles advancing from an electrical charge. In this way, from the moment a body acquires a charge, this information or novelty spreads rapidly in its environment, in fact at the speed of light, and can eventually reach another charge. Subsequently, the subject of the interaction between one charge and another begins to be dealt with, how it is possible to describe and study the fact from the interaction of charges with the field where it interacts.

In order to represent the electric field, the lines of force are used , which would be the vectors that leave the positive electric charges to enter the negative charges. Thus indicating the direction of the electric field force, which in turn would experiment with a point and positive charge, called a test charge. The number of lines of force would be proportional to the intensity of the electric field, since with the interaction of lines they are very close, the field is large and where they are separated, the field is small.

Researchers such as Michael Faraday , and later studies by James Clerk Maxwell , allowed the first descriptions of electrical phenomena, for example, Coulomb’s law , where only electrical charges were taken into account; to later develop more complete laws where the variation of the fields is studied.

What is an electric field for?

The electric field serves to reveal the interaction of charged particles and to determine the force on a charge located at that point.

Units of electric field

The unit of measurement for the intensity or magnitude of the electric field is used in volts per meter (v / m) .

Coulomb’s law can be used in the cases of electric fields, because it establishes what the force is like between two point electric charges, being a point electric charge the charge that is located at a geometric point at the spatial level. Remembering that it would be used for specific cases, since these charges must be at rest, generating electrostatics. This law studies the interaction between electrical charges that are particularly small compared to the distance between them.

Formula

The formula to calculate the electric field is as follows:

 

Where E is Electric Field Intensity, F is Force and q is Charge.

Types

There are three types of electric fields. The first is produced by a distribution of charge and is known as the electrostatic field . The second and third are associated with two types of magnetic induction , one produced by spatial movement with respect to magnetic flux and the other produced by bonding time that modifies magnetic flux.

Uniform electric field

The electric field consists of the area of ​​space where electric charges interact, these being of the same magnitude, sense and direction. For example, having two parallel charged plates, the electric field will be oriented from the plate with a positive electric charge towards the electric plate with a negative charge, causing the vector to not change.

Examples

• Electric lamps: An electric lamp when plugged into a current by an electric cable manages to generate electric fields in the air that surrounds said device. The higher voltage increases the intensity of the electric field. There may be voltage even if there is no active electrical current, since the electrical device is not required to be active for an electrical field to be generated around it.
• Radio and television transmitting and receiving antennas : From an emitting device of a radio station to a common radio, the message is transferred by means of an electric field, which is generated from antennas that capture the information and transmit it. Its most common form would be a metal rod. Each radio station has certain frequencies, which generate different electric fields, the operation occurs from the periodic movement of charges of electrical energy, which move from one end to another, generating an excess at one end of the antenna negatively charged while at the other extreme a deficit of positive charges is generated; they are exchanged from one extreme to the other, generating polarity.