Electric force


To be able to refer to the electric force we must also understand the concept of electric charge with which it is closely related. We know as an electric charge the property that some subatomic particles have, which occurs when they are related to others, it is an electromagnetic relationship that occurs through the positive and negative charges that a given particle has. We can say then, that between these two charges, a force is born which we know as the electric force which will depend on the value of the charge and thedistance that is separating them.


What is an electric force?

It is the force that appears or arises between two or more charges, the modulus of which will depend on the value of those charges and also on the distance that exists between them, separating them, while its sign will depend on each of the charges .

  • What does it consist of
  • How the electric force originates
  • features
  • Types of electrical force
  • Calculation
  • Address
  • Sense
  • Power lines
  • How it differs from magnetic force
  • Experiments
  • Importance of electric force
  • Examples

What does it consist of

The electrical force is the force that occurs between two electrical charges by means of attractive and repulsive forces, forces that do not exist in all types of charges. The concept of electric force was given by Charles Agustín de Coulomb in the year 1785 by means of a balance designed by himself, which sought to improve the compass used by sailors doing experiments with electric charges.


We can also define the concept of force as a magnitude vector which possesses the property of being able to change the way they have the object , to break their inertia , to modify its speed and power to change their state of rest , when put in motion . We could also say that force is any action or influence that has the ability to modify the state of rest or movement that a body possesses, giving it an acceleration that is capable of modifying its speed , direction.or felt , or, deforming it,

How the electric force originates

To understand how it originates, we must know that matter is made up of atoms which have a nucleus of protons and neutrons . At the periphery of the atom, the electrons are in orbits around the nucleus. Electrons from the farthest orbits can leave the atom and join a nearby one. The atom that has one less electron is positively charged, and the atom that has gained one electron is negatively charged.


  • It needs the interaction of at least two particles for it to exist.
  • It is directly proportional to the magnitude of the charges.
  • It is inversely proportional to the square of the distances that separate the charges.
  • It is referred by means of point loads .
  • It is a force that derives from a potential and can be attractive or repulsive .
  • It complies with the principle of superposition depending on the medium in which the loads are immersed.

Types of electrical force

  • Electrostatic force : includes charges without movement generating an electric field
  • Electromagnetic forces: they are the charges in motion , which usually electric fields depending on the form of movement.
  • Electrostatic force : it is what a body has when it is electrically charged .
  • Electromotive Force : o Voltage or Tension . It is the force with which theelectric current completes a circuit .


The electric force formula is as follows:

E = k q 1 q 2 / d 2


  • E = Electric force [N]
  • 1 , q 2 = Value of charges 1 and 2 [C]
  • d = distance of separation between charges [m]


When we refer to only two charges, the direction of the electric force is collinear to the line that joins them both.


The sense of the electric force between two charges is repulsion , when the two charges have the same sign and are attractive , when they have the opposite sign.

Power lines

After many investigations, it was considered that the electric field according to its physical properties can be represented by means of a series of imaginary lines of force , which are radial to the electric charges s but are also tangent to the direction of the electric field for any point, and this is the way in which the existence of the attractive or repulsive force is explained when electrified bodies interact.

There are several lines of force that emerge or leave the positive electrical charges , but at the same time enter the negative electrical charges , these lines of force have the following physical properties:

  • The lines of force of the electric field come from the positive electric charges and manage to enter the negative electric charges .
  • At all points in space, only one line of force passes , but when two or more of these points cross, then the resulting line of force must be calculated through a vector sum.
  • The density of electric field lines of force is proportional to the intensity of the electric field, which is known as Electric Flow.

How it differs from magnetic force

The electric force will always be in the direction of the electric field but the magnetic force is perpendicular to the field. The electric force works on a charged particle regardless of its speed, and the magnetic force acts only when the charged particle is in motion . The electric force does work when it displaces a charged particle, while the magnetic force associated with a magnetic fieldstationary does not do any kind of work. When a charge moves with velocity v, the applied magnetic field alters the direction of the velocity vector, but does not change the speed of the particle .


Several experiments can be done to test the electrical force, for example, if we rub a comb against our hair, it is observed that it attracts pieces of paper. The same effect occurs when rubbing other materials, such as amber with wool, glass, etc.

Importance of electric force

The importance of knowing the electric force and how it originates lies in the fact that it is a preliminary step to understand how the electric current , necessary for life, works. It also leads us to the induction of electromagnetics , a phenomenon that causes the production of an electromotive force .


  • On the TV screen , if when you turn it off you bring your arm or your head closer, you will see that the hairs are attracted.
  • When the glass is loaded by rubbing it with a cloth that attracts dust from the environment.

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